ICL3245

® ICL3225, ICL3245 Data Sheet February 27, 2006 FN4878.8 1 Microamp, +3V to +5.5V, 1Mbps, RS-232 Transceivers with Enhanced Automatic Powerdown The Intersil ICL32XX devices are 3.0V to 5.5V powered RS-232 transmitters/receivers which meet ElA/TIA-232 and V.28/V.24 specifications, even at VCC = 3.0V. Targeted applications are PDAs, Palmtops, and notebook and laptop computers where the low operational, and even lower standby, power consumption is critical. Efficient on-chip charge pumps, coupled with manual and enhanced automatic powerdown functions, reduce the standby supply current to a 1µA trickle. Small footprint packaging, and the use of small, low value capacitors ensure board space savings as well. Data rates greater than 1Mbps are guaranteed at worst case load conditions. This family is fully compatible with 3.3V only systems, mixed 3.3V and 5.0V systems, and 5.0V only systems. The ICL3245 is a 3 driver, 5 receiver device that provides a complete serial port suitable for laptop or notebook computers. It also includes a noninverting always-active receiver for “wake-up” capability. These devices, feature an enhanced automatic powerdown function which powers down the on-chip powersupply and driver circuits. This occurs when all receiver and transmitter inputs detect no signal transitions for a period of 30s. These devices power back up, automatically, whenever they sense a transition on any transmitter or receiver input. Table 1 summarizes the features of the device represented by this data sheet, while Application Note AN9863 summarizes the features of each device comprising the ICL32XX 3V family. Features • ±15kV ESD Protected (Human Body Model) • Manual and Enhanced Automatic Powerdown Features • Drop in Replacements for MAX3225, MAX3245 • Meets EIA/TIA-232 and V.28/V.24 Specifications at 3V • Latch-Up Free • On-Chip Voltage Converters Require Only Four External 0.1µF Capacitors • Guaranteed Mouse Driveability (ICL3245) • “Ready to Transmit” Indicator Output (ICL3225) • Receiver Hysteresis For Improved Noise Immunity • Guaranteed Minimum Data Rate . . . . . . . . . . . . . . 1Mbps • Low Skew at Transmitter/Receiver Input Trip Points . . . 10ns • Guaranteed Minimum Slew Rate . . . . . . . . . . . . . . 24V/µs • Wide Power Supply Range. . . . . . . . Single +3V to +5.5V • Low Supply Current in Powerdown State . . . . . . . . . . .1µA • Pb-Free Plus Anneal Available (RoHS Compliant) Applications • Any System Requiring RS-232 Communication Ports - Battery Powered, Hand-Held, and Portable Equipment - Laptop Computers, Notebooks, Palmtops - Modems, Printers and other Peripherals - Digital Cameras - Cellular/Mobile Phones Related Literature • Technical Brief TB363 “Guidelines for Handling and Processing Moisture Sensitive Surface Mount Devices (SMDs)” TABLE 1. SUMMARY OF FEATURES NO. OF MONITOR Rx. (ROUTB) 0 1 DATA RATE (kbps) 1000 1000 MANUAL POWERDOWN? Yes Yes ENHANCED AUTOMATIC POWERDOWN FUNCTION? Yes Yes PART NUMBER ICL3225 ICL3245 NO. OF NO. OF Tx. Rx. 2 3 2 5 Rx. ENABLE FUNCTION? No No READY OUTPUT? Yes No 1 CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 1-888-468-3774 | Intersil (and design) is a registered trademark of Intersil Americas Inc. Copyright © Intersil Americas Inc. 2000, 2001, 2003-2006. All Rights Reserved All other trademarks mentioned are the property of their respective owners. ICL3225, ICL3245 Ordering Information PART NO. ICL3225CA ICL3225CA-T ICL3225CAZ (Note) ICL3225CAZ-T (Note) ICL3225CP ICL3225CPZ (Note) ICL3225IA ICL3225IA-T ICL3225IAZ (Note) ICL3225IAZ-T (Note) ICL3245CA ICL3245CA-T ICL3245IV ICL3245IV-T PART MARKING ICL3225CA ICL3225CA ICL3225CAZ ICL3225CAZ ICL3225CP ICL3225CPZ ICL3225IA ICL3225IA ICL3225IAZ ICL3225IAZ ICL3245CA ICL3245CA ICL3245IV ICL3245IV TEMP. RANGE (°C) 0 to 70 0 to 70 0 to 70 0 to 70 0 to 70 0 to 70 -40 to 85 -40 to 85 -40 to 85 -40 to 85 0 to 70 0 to 70 -40 to 85 -40 to 85 20 Ld SSOP 20 Ld SSOP Tape and Reel 20 Ld SSOP (Pb-free) 20 Ld SSOP Tape and Reel (Pb-free) 20 Ld PDIP 20 Ld PDIP* (Pb-free) 20 Ld SSOP 20 Ld SSOP Tape and Reel 20 Ld SSOP (Pb-free) 20 Ld SSOP Tape and Reel (Pb-free) 28 Ld SSOP 28 Ld SSOP Tape and Reel 28 Ld TSSOP 28 Ld TSSOP Tape and Reel PACKAGE PKG. DWG. # M20.209 M20.209 M20.209 M20.209 E20.3 E20.3 M20.209 M20.209 M20.209 M20.209 M28.209 M28.209 M28.173 M28.173 *Pb-free PDIPs can be used for through hole wave solder processing only. They are not intended for use in Reflow solder processing applications. NOTE: Intersil Pb-free plus anneal products employ special Pb-free material sets; molding compounds/die attach materials and 100% matte tin plate termination finish, which are RoHS compliant and compatible with both SnPb and Pb-free soldering operations. Intersil Pb-free products are MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020. Pinouts ICL3225 (PDIP, SSOP) TOP VIEW READY 1 20 FORCEOFF 19 VCC 18 GND 17 T1OUT 16 R1IN 15 R1OUT 14 FORCEON 13 T1IN 12 T2IN 11 INVALID ICL3245 (SSOP, TSSOP) TOP VIEW C2+ 1 C2- 2 V3 28 C1+ 27 V+ 26 VCC 25 GND 24 C123 FORCEON 22 FORCEOFF 21 INVALID 20 R2OUTB 19 R1OUT 18 R2OUT 17 R3OUT 16 R4OUT 15 R5OUT C1+ 2 V+ 3 C1- 4 C2+ 5 C2- 6 V7 R1IN 4 R2IN 5 R3IN 6 R4IN 7 R5IN 8 T1OUT 9 T2OUT 10 T3OUT 11 T3IN 12 T2IN 13 T1IN 14 T2OUT 8 R2IN 9 R2OUT 10 2 FN4878.8 February 27, 2006 ICL3225, ICL3245 Pin Descriptions PIN VCC V+ VGND C1+ C1C2+ C2TIN TOUT RIN ROUT ROUTB INVALID READY System power supply input (3.0V to 5.5V). Internally generated positive transmitter supply (+5.5V). Internally generated negative transmitter supply (-5.5V). Ground connection. External capacitor (voltage doubler) is connected to this lead. External capacitor (voltage doubler) is connected to this lead. External capacitor (voltage inverter) is connected to this lead. External capacitor (voltage inverter) is connected to this lead. TTL/CMOS compatible transmitter Inputs. RS-232 level (nominally ±5.5V) transmitter outputs. RS-232 compatible receiver inputs. TTL/CMOS level receiver outputs. TTL/CMOS level, noninverting, always enabled receiver outputs. Active low output that indicates if no valid RS-232 levels are present on any receiver input. Active high output that indicates when the ICL32XXE is ready to transmit (i.e., V- ≤ -4V) FUNCTION FORCEOFF Active low to shut down transmitters and on-chip power supply. This overrides any automatic circuitry and FORCEON (see Table 2). FORCEON Active high input to override automatic powerdown circuitry thereby keeping transmitters active. (FORCEOFF must be high). Typical Operating Circuits ICL3225 +3.3V + 0.1µF 2 + 4 5 + 6 13 C1+ C1C2+ C2- 19 VCC V+ 3 + C3 0.1µF C4 0.1µF + T1OUT T2OUT R1IN RS-232 LEVELS C1 0.1µF C2 0.1µF V- 7 T1 T2 17 T1IN T2IN TTL/CMOS LOGIC LEVELS R1OUT 12 8 15 R1 5kΩ 16 R2OUT 10 R2 1 READY 14 FORCEON GND 18 FORCEOFF INVALID 5kΩ 9 R2IN 20 11 VCC TO POWER CONTROL LOGIC 3 FN4878.8 February 27, 2006 ICL3225, ICL3245 Typical Operating Circuits (Continued) ICL3245 +3.3V + 0.1µF C1 0.1µF C2 0.1µF + 26 28 24 C1+ VCC 27 V+ 3 + C3 0.1µF C11 C2+ + 2 C214 T1 V- C4 0.1µF + T1OUT 9 T1IN 13 T2IN 12 T3IN 20 R2OUTB TTL/CMOS LOGIC LEVELS 19 R1OUT R1 18 R2OUT R2 17 R3OUT R3 16 R4OUT R4 15 R5OUT 23 22 FORCEOFF 21 INVALID GND 25 R5 FORCEON VCC TO POWER CONTROL LOGIC 5kΩ 5kΩ 8 5kΩ 7 5kΩ 6 5kΩ 5 4 T3 11 T2 10 T2OUT RS-232 LEVELS T3OUT R1IN R2IN R3IN RS-232 LEVELS R4IN R5IN 4 FN4878.8 February 27, 2006 ICL3225, ICL3245 Absolute Maximum Ratings VCC to Ground. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 6V V+ to Ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 7V V- to Ground. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +0.3V to -7V V+ to V- . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14V Input Voltages TIN, FORCEOFF, FORCEON. . . . . . . . . . . . . . . . . . . -0.3V to 6V RIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±25V Output Voltages TOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±13.2V ROUT, INVALID, READY. . . . . . . . . . . . . . . . . -0.3V to VCC +0.3V Short Circuit Duration TOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Continuous ESD Rating . . . . . . . . . . . . . . . . . . . . . . . . . See Specification Table Thermal Information Thermal Resistance (Typical, Note 1) θJA (°C/W) 20 Ld PDIP Package*. . . . . . . . . . . . . . . . . . . . . . . . 80 20 Ld SSOP Package . . . . . . . . . . . . . . . . . . . . . . . 135 28 Ld SSOP Package . . . . . . . . . . . . . . . . . . . . . . . 100 28 Ld TSSOP Package . . . . . . . . . . . . . . . . . . . . . . 125 Maximum Junction Temperature (Plastic Package) . . . . . . . 150°C Maximum Storage Temperature Range . . . . . . . . . . . -65°C to 150°C Maximum Lead Temperature (Soldering 10s) . . . . . . . . . . . . 300°C (SSOP, TSSOP - Lead Tips Only) *Pb-free PDIPs can be used for through hole wave solder processing only. They are not intended for use in Reflow solder processing applications. Operating Conditions Temperature Range ICL32XXC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0°C to 70°C ICL32XXI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -40°C to 85°C CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. NOTE: 1. θJA is measured with the component mounted on a low effective thermal conductivity test board in free air. See Tech Brief TB379 for details. Electrical Specifications Test Conditions: VCC = 3V to 5.5V, C1 - C4 = 0.1µF; Unless Otherwise Specified. Typicals are at TA = 25°C TEST CONDITIONS TEMP (°C) MIN TYP MAX UNITS µA µA mA mA PARAMETER DC CHARACTERISTICS Supply Current, Automatic Powerdown Supply Current, Powerdown Supply Current, Automatic Powerdown Disabled All RIN Open, FORCEON = GND, FORCEOFF = VCC FORCEOFF = GND All Outputs Unloaded, ICL3245, VCC = 3.0V FORCEON = FORCEOFF = VCC ICL322X, V CC = 3.15V TIN, FORCEON, FORCEOFF TIN, FORCEON, FORCEOFF VCC = 3.3V VCC = 5.0V 25 25 25 25 - 1.0 1.0 0.3 0.3 10 10 1.0 1.0 LOGIC AND TRANSMITTER INPUTS AND RECEIVER OUTPUTS Input Logic Threshold Low Input Logic Threshold High Full Full Full 25 TIN, FORCEON, FORCEOFF FORCEOFF = GND IOUT = 1.6mA IOUT = -1.0mA Full Full Full Full 2.0 2.4 0.5 ±0.01 ±0.05 0.8 ±1.0 ±10 0.4 V V V V µA µA V V Transmitter Input Hysteresis Input Leakage Current Output Leakage Current Output Voltage Low Output Voltage High RECEIVER INPUTS Input Voltage Range Input Threshold Low VCC = 3.3V VCC = 5.0V Input Threshold High VCC = 3.3V VCC = 5.0V Input Hysteresis Input Resistance TRANSMITTER OUTPUTS Output Voltage Swing Output Resistance Output Short-Circuit Current All Transmitter Outputs Loaded with 3kΩ to Ground VCC = V+ = V- = 0V, Transmitter Output = ±2V VCC -0.6 VCC -0.1 -25 0.6 0.8 3 ±5.0 300 1.2 1.5 1.5 1.8 0.5 5 ±5.4 10M ±35 Full 25 25 25 25 25 25 25 2.4 2.4 7 V V V V V V kΩ Full Full Full ±60 V Ω mA 5 FN4878.8 February 27, 2006 ICL3225, ICL3245 Electrical Specifications Test Conditions: VCC = 3V to 5.5V, C1 - C4 = 0.1µF; Unless Otherwise Specified. Typicals are at TA = 25°C (Continued) TEST CONDITIONS VOUT = ±12V, VCC = 0V or 3V to 5.5V Automatic Powerdown or FORCEOFF = GND T1IN = T2IN = GND, T3IN = VCC, T3OUT Loaded with 3kΩ to GND, T1OUT and T2OUT Loaded with 2.5mA Each See Figure 6 See Figure 6 IOUT = 1.6mA IOUT = -1.0mA TEMP (°C) Full MIN TYP MAX UNITS ±25 µA PARAMETER Output Leakage Current MOUSE DRIVEABILITY Transmitter Output Voltage (See Figure 11) Full ±5 - - V ENHANCED AUTOMATIC POWERDOWN (FORCEON = GND, FORCEOFF = VCC) Receiver Input Thresholds to INVALID High Receiver Input Thresholds to INVALID Low INVALID, READY Output Voltage Low INVALID, READY Output Voltage High Receiver Positive or Negative Threshold to INVALID High Delay (tINVH) Receiver Positive or Negative Threshold to INVALID Low Delay (tINVL) Receiver or Transmitter Edge to Transmitters Enabled Delay (tWU) Receiver or Transmitter Edge to Transmitters Disabled Delay (tAUTOPWDN) TIMING CHARACTERISTICS Maximum Data Rate RL = 3kΩ, One Transmitter Switching CL = 1000pF VCC = 3V to 4.5V, CL = 250pF VCC = 4.5V to 5.5V, CL = 1000pF Receiver Propagation Delay Receiver Input to Receiver Output, CL = 150pF Normal Operation Normal Operation tPHL - tPLH (Note 3) tPHL - tPLH (Note 3) VCC = 3.3V, RL = 3kΩ to 7kΩ, Measured from 3V to -3V or -3V to 3V, CL = 150pF to 1000pF Human Body Model IEC61000-4-2 Contact Discharge IEC61000-4-2 Air Gap Discharge All Other Pins Human Body Model tPHL tPLH Full Full Full 25 25 25 25 25 25 25 250 1000 1000 24 0.15 0.15 200 200 25 50 150 kbps kbps kbps µs µs ns ns ns ns V/µs Note 2 Note 2 Full Full Full Full 25 -2.7 -0.3 VCC-0.6 1 2.7 0.3 0.4 V V V V µs 25 - 30 - µs 25 Full 15 100 30 60 µs sec Receiver Output Enable Time Receiver Output Disable Time Transmitter Skew Receiver Skew Transition Region Slew Rate ESD PERFORMANCE RS-232 Pins (TOUT, RIN) 25 25 25 25 - ±15 ±8 > ±8 ±2.5 - kV kV kV kV NOTES: 2. An “edge” is defined as a transition through the transmitter or receiver input thresholds. 3. Skews are measured at the receiver input switching points (1.4V). 6 FN4878.8 February 27, 2006 ICL3225, ICL3245 Detailed Description These ICL32XX interface ICs operate from a single +3V to +5.5V supply, guarantee a 1Mbps minimum data rate, require only four small external 0.1µF capacitors, feature low power consumption, and meet all ElA RS-232C and V.28 specifications. The circuit is divided into three sections: The charge pump, the transmitters, and the receivers. Schmitt trigger input stage uses hysteresis to increase noise immunity and decrease errors due to slow input signal transitions. The ICL3245 inverting receivers disable during forced (manual) powerdown, but not during automatic powerdown (see Table 2). Conversely, the monitor receiver remains active even during manual powerdown making it extremely useful for Ring Indicator monitoring. Standard receivers driving powered down peripherals must be disabled to prevent current flow through the peripheral’s protection diodes (see Figures 2 and 3). This renders them useless for wake up functions, but the corresponding monitor receiver can be dedicated to this task as shown in Figure 3. VCC RXIN -25V ≤ VRIN ≤ +25V GND 5kΩ RXOUT GND ≤ VROUT ≤ VCC Charge-Pump Intersil’s new ICL32XX family utilizes regulated on-chip dual charge pumps as voltage doublers, and voltage inverters to generate ±5.5V transmitter supplies from a VCC supply as low as 3.0V. This allows these devices to maintain RS-232 compliant output levels over the ±10% tolerance range of 3.3V powered systems. The efficient on-chip power supplies require only four small, external 0.1µF capacitors for the voltage doubler and inverter functions at VCC = 3.3V. See the “Capacitor Selection” section, and Table 3 for capacitor recommendations for other operating conditions. The charge pumps operate discontinuously (i.e., they turn off as soon as the V+ and V- supplies are pumped up to the nominal values), resulting in significant power savings. FIGURE 1. INVERTING RECEIVER CONNECTIONS VCC Transmitters The transmitters are proprietary, low dropout, inverting drivers that translate TTL/CMOS inputs to EIA/TIA-232 output levels. Coupled with the on-chip ±5.5V supplies, these transmitters deliver true RS-232 levels over a wide range of single supply system voltages. Transmitter outputs disable and assume a high impedance state when the device enters the powerdown mode (see Table 2). These outputs may be driven to ±12V when disabled. All devices guarantee a 1Mbps data rate for full load conditions (3kΩ and 250pF), VCC ≥ 3.0V, with one transmitter operating at full speed. Under more typical conditions of VCC ≥ 3.3V, RL = 3kΩ, and CL = 250pF, one transmitter easily operates at 1.4Mbps. Transmitter skew is extremely low on these devices, and is specified at the receiver input trip points (1.4V), rather than the arbitrary 0V crossing point typical of other RS-232 families. Transmitter inputs float if left unconnected, and may cause ICC increases. Connect unused inputs to GND for the best performance. VCC VOUT = VCC Rx POWERED DOWN UART Tx GND SHDN = GND VCC CURRENT FLOW OLD RS-232 CHIP FIGURE 2. POWER DRAIN THROUGH POWERED DOWN PERIPHERAL VCC TRANSITION DETECTOR TO WAKE-UP LOGIC VCC ICL3245 Receivers All the ICL32XX devices contain standard inverting receivers, but only the ICL3245 receivers can three-state, via the FORCEOFF control line. Additionally, the ICL3245 includes a noninverting (monitor) receiver (denoted by the ROUTB label) that is always active, regardless of the state of any control lines. Both receiver types convert RS-232 signals to CMOS output levels and accept inputs up to ±25V while presenting the required 3kΩ to 7kΩ input impedance (see Figure 1) even if the power is off (VCC = 0V). The receivers’ 7 RX POWERED DOWN UART R2OUTB VOUT = HI-Z R2OUT TX T1IN T1OUT FORCEOFF = GND R2IN FIGURE 3. DISABLED RECEIVERS PREVENT POWER DRAIN FN4878.8 February 27, 2006 ICL3225, ICL3245 TABLE 2. POWERDOWN LOGIC TRUTH TABLE RCVR OR XMTR EDGE WITHIN 30s? ICL3225 NO NO YES YES NO NO X X H H H H H H L L H H L L L L X X Active Active Active Active High-Z High-Z High-Z High-Z Active Active Active Active Active Active Active Active N.A. N.A. N.A. N.A. N.A. N.A. N.A. N.A. No Yes No Yes No Yes No Yes L H L H L H L H Normal Operation (Enhanced Auto Powerdown Disabled) Normal Operation (Enhanced Auto Powerdown Enabled) Powerdown Due to Enhanced Auto Powerdown Logic Manual Powerdown RS-232 LEVEL PRESENT AT RECEIVER INPUT? (NOTE 4) FORCEOFF FORCEON TRANSMITTER RECEIVER ROUTB INPUT INPUT OUTPUTS OUTPUTS OUTPUTS INVALID OUTPUT MODE OF OPERATION ICL322X - INVALID DRIVING FORCEON AND FORCEOFF (EMULATES AUTOMATIC POWERDOWN) X X ICL3245 NO NO YES YES NO NO X X H H H H H H L L H H L L L L X X Active Active Active Active High-Z High-Z High-Z High-Z Active Active Active Active Active Active High-Z High-Z Active Active Active Active Active Active Active Active No Yes No Yes No Yes No Yes L H L H L H L H Normal Operation (Enhanced Auto Powerdown Disabled) Normal Operation (Enhanced Auto Powerdown Enabled) Powerdown Due to Enhanced Auto Powerdown Logic Manual Powerdown NOTE 5 NOTE 5 NOTE 5 NOTE 5 Active High-Z Active Active N.A. N.A. Yes No H L Normal Operation Forced Auto Powerdown ICL3245 - INVALID DRIVING FORCEON AND FORCEOFF (EMULATES AUTOMATIC POWERDOWN) X X NOTES: 4. Applies only to the ICL3245. 5. Input is connected to INVALID Output. NOTE 5 NOTE 5 NOTE 5 NOTE 5 Active High-Z Active High-Z Active Active Yes No H L Normal Operation Forced Auto Powerdown Powerdown Functionality This 3V family of RS-232 interface devices requires a nominal supply current of 0.3mA during normal operation (not in powerdown mode). This is considerably less than the 5mA to 11mA current required of 5V RS-232 devices. The already low current requirement drops significantly when the device enters powerdown mode. In powerdown, supply current drops to 1µA, because the on-chip charge pump turns off (V+ collapses to VCC, V- collapses to GND), and the transmitter outputs three-state. Inverting receiver outputs may or may not disable in powerdown; refer to Table 2 for details. This micro-power mode makes these devices ideal for battery powered and portable applications. where the FORCEON and FORCEOFF inputs determine the IC’s mode. For always enabled operation, FORCEON and FORCEOFF are both strapped high. To switch between active and powerdown modes, under logic or software control, only the FORCEOFF input need be driven. The FORCEON state isn’t critical, as FORCEOFF dominates over FORCEON. Nevertheless, if strictly manual control over powerdown is desired, the user must strap FORCEON high to disable the enhanced automatic powerdown circuitry. ICL3245 inverting (standard) receiver outputs also disable when the device is in powerdown, thereby eliminating the possible current path through a shutdown peripheral’s input protection diode (see Figures 2 and 3). Connecting FORCEOFF and FORCEON together disables the enhanced automatic powerdown feature, enabling them to function as a manual SHUTDOWN input (see Figure 4). Software Controlled (Manual) Powerdown These three devices allow the user to force the IC into the low power, standby state, and utilize a two pin approach 8 FN4878.8 February 27, 2006 ICL3225, ICL3245 FORCEOFF PWR MGT LOGIC FORCEON INVALID ICL32XX I/O UART CPU floating (but pulled to GND by the internal receiver pull down resistors), the INVALID logic detects the invalid levels and drives the output low. The power management logic then uses this indicator to power down the interface block. Reconnecting the cable restores valid levels at the receiver inputs, INVALID switches high, and the power management logic wakes up the interface block. INVALID can also be used to indicate the DTR or RING INDICATOR signal, as long as the other receiver inputs are floating, or driven to GND (as in the case of a powered down driver). VALID RS-232 LEVEL - INVALID = 1 2.7V INDETERMINATE FIGURE 4. CONNECTIONS FOR MANUAL POWERDOWN WHEN NO VALID RECEIVER SIGNALS ARE PRESENT 0.3V INVALID LEVEL - INVALID = 0 -0.3V INDETERMINATE With any of the above control schemes, the time required to exit powerdown, and resume transmission is only 100µs. When using both manual and enhanced automatic powerdown (FORCEON = 0), the ICL32XX won’t power up from manual powerdown until both FORCEOFF and FORCEON are driven high, or until a transition occurs on a receiver or transmitter input. Figure 5 illustrates a circuit for ensuring that the ICL32XX powers up as soon as FORCEOFF switches high. The rising edge of the Master Powerdown signal forces the device to power up, and the ICL32XX returns to enhanced automatic powerdown mode an RC time constant after this rising edge. The time constant isn’t critical, because the ICL32XX remains powered up for 30 seconds after the FORCEON falling edge, even if there are no signal transitions. This gives slow-to-wake systems (e.g., a mouse) plenty of time to start transmitting, and as long as it starts transmitting within 30 seconds both systems remain enabled. POWER MANAGEMENT UNIT MASTER POWERDOWN LINE 0.1µF 1MΩ -2.7V VALID RS-232 LEVEL - INVALID = 1 FIGURE 6. DEFINITION OF VALID RS-232 RECEIVER LEVELS Enhanced Automatic Powerdown Even greater power savings is available by using these devices which feature an enhanced automatic powerdown function. When the enhanced powerdown logic determines that no transitions have occurred on any of the transmitter nor receiver inputs for 30 seconds, the charge pump and transmitters powerdown, thereby reducing supply current to 1µA. The ICL32XX automatically powers back up whenever it detects a transition on one of these inputs. This automatic powerdown feature provides additional system power savings without changes to the existing operating system. Enhanced automatic powerdown operates when the FORCEON input is low, and the FORCEOFF input is high. Tying FORCEON high disables automatic powerdown, but manual powerdown is always available via the overriding FORCEOFF input. Table 2 summarizes the enhanced automatic powerdown functionality. FORCEOFF T_IN EDGE DETECT S 30s TIMER EDGE DETECT R AUTOSHDN FORCEOFF FORCEON ICL32XX FIGURE 5. CIRCUIT TO ENSURE IMMEDIATE POWER UP WHEN EXITING FORCED POWERDOWN INVALID Output The INVALID output always indicates (see Table 2) whether or not 30µs have elapsed with invalid RS-232 signals (see Figures 6 and 8) persisting on all of the receiver inputs, giving the user an easy way to determine when the interface block should power down. Invalid receiver levels occur whenever the driving peripheral’s outputs are shut off (powered down) or when the RS-232 interface cable is disconnected. In the case of a disconnected interface cable where all the receiver inputs are 9 R_IN FORCEON FIGURE 7. ENHANCED AUTOMATIC POWERDOWN LOGIC FN4878.8 February 27, 2006 ICL3225, ICL3245 RECEIVER INPUTS TRANSMITTER INPUTS TRANSMITTER OUTPUTS tINVH INVALID OUTPUT tINVL tAUTOPWDN READY OUTPUT V+ VCC 0 VtWU tAUTOPWDN tWU } INVALID REGION FIGURE 8. ENHANCED AUTOMATIC POWERDOWN, INVALID AND READY TIMING DIAGRAMS Figure 7 illustrates the enhanced powerdown control logic. Note that once the ICL32XX enters powerdown (manually or automatically), the 30 second timer remains timed out (set), keeping the ICL32XX powered down until FORCEON transitions high, or until a transition occurs on a receiver or transmitter input. The INVALID output signal switches low to indicate that invalid levels have persisted on all of the receiver inputs for more than 30µs (see Figure 8), but this has no direct effect on the state of the ICL32XX (see the next sections for methods of utilizing INVALID to power down the device). INVALID switches high 1µs after detecting a valid RS-232 level on a receiver input. INVALID operates in all modes (forced or automatic powerdown, or forced on), so it is also useful for systems employing manual powerdown circuitry. The time to recover from automatic powerdown mode is typically 100µs. another computer via a detachable cable. Detaching the cable allows the internal receiver pull-down resistors to pull the inputs to GND (an invalid RS-232 level), causing the 30µs timer to time-out and drive the IC into powerdown. Reconnecting the cable restores valid levels, causing the IC to power back up. FORCEOFF FN4878.8 February 27, 2006 ICL32XX I/O UART CPU Emulating Standard Automatic Powerdown If enhanced automatic powerdown isn’t desired, the user can implement the standard automatic powerdown feature (mimics the function on the ICL3221/ICL3223/ICL3243) by connecting the INVALID output to the FORCEON and FORCEOFF inputs, as shown in Figure 9. After 30µs of invalid receiver levels, INVALID switches low and drives the ICL32XX into a forced powerdown condition. INVALID switches high as soon as a receiver input senses a valid RS232 level, forcing the ICL32XX to power on. See the “INVALID DRIVING FORCEON AND FORCEOFF” section of Table 2 for an operational summary. This operational mode is perfect for handheld devices that communicate with FIGURE 9. CONNECTIONS FOR AUTOMATIC POWERDOWN WHEN NO VALID RECEIVER SIGNALS ARE PRESENT Hybrid Automatic Powerdown Options For devices which communicate only through a detachable cable, connecting INVALID to FORCEOFF (with FORCEON = 0) may be a desirable configuration. While the cable is attached INVALID and FORCEOFF remain high, so the enhanced automatic powerdown logic powers down the RS232 device whenever there is 30 seconds of inactivity on the 10 FORCEON INVALID ICL3225, ICL3245 receiver and transmitter inputs. Detaching the cable allows the receiver inputs to drop to an invalid level (GND), so INVALID switches low and forces the RS-232 device to power down. The ICL32XX remains powered down until the cable is reconnected (INVALID = FORCEOFF = 1) and a transition occurs on a receiver or transmitter input (see Figure 7). For immediate power up when the cable is reattached, connect FORCEON to FORCEOFF through a network similar to that shown in Figure 5. Transmitter Outputs when Exiting Powerdown Figure 10 shows the response of two transmitter outputs when exiting powerdown mode. As they activate, the two transmitter outputs properly go to opposite RS-232 levels, with no glitching, ringing, nor undesirable transients. Each transmitter is loaded with 3kΩ in parallel with 2500pF. Note that the transmitters enable only when the magnitude of the supplies exceed approximately 3V. Ready Output (ICL3225 Only) The Ready output indicates that the ICL322X is ready to transmit. Ready switches low whenever the device enters powerdown, and switches back high during power-up when V- reaches -4V or lower. 5V/DIV. FORCEOFF T1 Capacitor Selection The charge pumps require 0.1µF capacitors for 3.3V operation. For other supply voltages refer to Table 3 for capacitor values. Do not use values smaller than those listed in Table 3. Increasing the capacitor values (by a factor of 2) reduces ripple on the transmitter outputs and slightly reduces power consumption. C2, C3, and C4 can be increased without increasing C1’s value, however, do not increase C1 without also increasing C2, C3, and C4 to maintain the proper ratios (C1 to the other capacitors). When using minimum required capacitor values, make sure that capacitor values do not degrade excessively with temperature. If in doubt, use capacitors with a larger nominal value. The capacitor’s equivalent series resistance (ESR) usually rises at low temperatures and it influences the amount of ripple on V+ and V-. TABLE 3. REQUIRED CAPACITOR VALUES VCC (V) 3.0 to 3.6 4.5 to 5.5 3.0 to 5.5 C1 (µF) 0.1 0.047 0.1 C2, C3, C4 (µF) 0.1 TRANSMITTER OUTPUT VOLTAGE (V) 2V/DIV VCC = +3.3V C1 - C4 = 0.1µF T2 5V/DIV. READY TIME (20µs/DIV.) FIGURE 10. TRANSMITTER OUTPUTS WHEN EXITING POWERDOWN Mouse Driveability The ICL3245 is specifically designed to power a serial mouse while operating from low voltage supplies. Figure 11 shows the transmitter output voltages under increasing load current. The on-chip switching regulator ensures the transmitters will supply at least ±5V during worst case conditions (15mA for paralleled V+ transmitters, 7.3mA for single V- transmitter). 6 5 4 3 2 1 0 -1 -2 -3 -4 -5 -6 0 1 2 3 4 5 6 7 8 9 10 VCC T3 T2 ICL3245 VOUT VOUT VCC = 3.0V T1 VOUT+ VOUT+ 0.33 0.47 Power Supply Decoupling In most circumstances a 0.1µF bypass capacitor is adequate. In applications that are particularly sensitive to power supply noise, decouple VCC to ground with a capacitor of the same value as the charge-pump capacitor C1. Connect the bypass capacitor as close as possible to the IC. Operation Down to 2.7V ICL32XXE transmitter outputs meet RS-562 levels (±3.7V), at full data rate, with VCC as low as 2.7V. RS-562 levels typically ensure inter operability with RS-232 devices. LOAD CURRENT PER TRANSMITTER (mA) FIGURE 11. TRANSMITTER OUTPUT VOLTAGE vs LOAD CURRENT (PER TRANSMITTER, i.e., DOUBLE CURRENT AXIS FOR TOTAL VOUT+ CURRENT) 11 FN4878.8 February 27, 2006 ICL3225, ICL3245 High Data Rates The ICL32XX maintain the RS-232 ±5V minimum transmitter output voltages even at high data rates. Figure 12 details a transmitter loopback test circuit, and Figure 13 illustrates the loopback test result at 250kbps. For this test, all transmitters were simultaneously driving RS-232 loads in parallel with 1000pF, at 250kbps. Figure 14 shows the loopback results for a single transmitter driving 250pF and an RS-232 load at 1Mbps. The static transmitters were also loaded with an RS-232 receiver. VCC 0.1µF + 5V/DIV. T1IN T1OUT R1OUT VCC = +3.3V C1 - C4 = 0.1µF 0.5µs/DIV. VCC V+ + C1 C1+ C1- + C3 FIGURE 14. LOOPBACK TEST AT 1Mbps (CL = 250pF) ICL32XX + C2 C2TIN ROUT FORCEON VCC FORCEOFF TOUT RIN 5K CL C2+ VC4 + Interconnection with 3V and 5V Logic The ICL32XXE directly interfaces with 5V CMOS and TTL logic families. Nevertheless, with the ICL32XX at 3.3V, and the logic supply at 5V, AC, HC, and CD4000 outputs can drive ICL32XX inputs, but ICL32XX outputs do not reach the minimum VIH for these logic families. See Table 4 for more information. TABLE 4. LOGIC FAMILY COMPATIBILITY WITH VARIOUS SUPPLY VOLTAGES VCC SYSTEM POWER-SUPPLY SUPPLY VOLTAGE VOLTAGE (V) (V) 3.3 5 5 3.3 5 3.3 FIGURE 12. TRANSMITTER LOOPBACK TEST CIRCUIT COMPATIBILITY Compatible with all CMOS families. Compatible with all TTL and CMOS logic families. Compatible with ACT and HCT CMOS, and with TTL. ICL32XX outputs are incompatible with AC, HC, and CD4000 CMOS inputs. 5V/DIV. T1IN T1OUT R1OUT VCC = +3.3V C1 - C4 = 0.1µF 2µs/DIV. FIGURE 13. LOOPBACK TEST AT 250kbps (CL = 1000pF) 12 FN4878.8 February 27, 2006 ICL3225, ICL3245 Typical Performance Curves 6 TRANSMITTER OUTPUT VOLTAGE (V) 4 2 1 TRANSMITTER AT 1Mbps OTHER TRANSMITTERS AT 30kbps 0 -2 VOUT -4 10 -6 0 1000 2000 3000 4000 5000 LOAD CAPACITANCE (pF) 0 0 1000 2000 3000 4000 5000 LOAD CAPACITANCE (pF) VCC = 3.3V, TA = 25°C 110 VOUT+ SLEW RATE (V/µs) 90 +SLEW 70 50 -SLEW 30 FIGURE 15. TRANSMITTER OUTPUT VOLTAGE vs LOAD CAPACITANCE FIGURE 16. SLEW RATE vs LOAD CAPACITANCE 90 ICL3225 80 1Mbps SUPPLY CURRENT (mA) SUPPLY CURRENT (mA) 70 60 50 40 30 120kbps 20 10 0 1000 2000 3000 4000 5000 LOAD CAPACITANCE (pF) 90 ICL3245 80 70 60 50 40 30 20 10 0 250kbps 1Mbps 250kbps 120kbps 1000 2000 3000 4000 5000 LOAD CAPACITANCE (pF) FIGURE 17. SUPPLY CURRENT vs LOAD CAPACITANCE WHEN TRANSMITTING DATA FIGURE 18. SUPPLY CURRENT vs LOAD CAPACITANCE WHEN TRANSMITTING DATA 13 FN4878.8 February 27, 2006 ICL3225, ICL3245 Typical Performance Curves VCC = 3.3V, TA = 25°C (Continued) 3.5 3.0 SUPPLY CURRENT (mA) 2.5 2.0 1.5 1.0 0.5 0 2.5 NO LOAD ALL OUTPUTS STATIC 3.0 3.5 4.0 4.5 5.0 5.5 6.0 SUPPLY VOLTAGE (V) FIGURE 19. SUPPLY CURRENT vs SUPPLY VOLTAGE Die Characteristics SUBSTRATE POTENTIAL (POWERED UP) GND TRANSISTOR COUNT ICL3225: 937 ICL3245: 1109 PROCESS Si Gate CMOS 14 FN4878.8 February 27, 2006 ICL3225, ICL3245 Dual-In-Line Plastic Packages (PDIP) N E1 INDEX AREA 12 3 N/2 -B-AD BASE PLANE SEATING PLANE D1 B1 B 0.010 (0.25) M D1 A1 A2 L A C L E E20.3 (JEDEC MS-001-AD ISSUE D) 20 LEAD DUAL-IN-LINE PLASTIC PACKAGE INCHES SYMBOL A A1 MIN 0.015 0.115 0.014 0.045 0.008 0.980 0.005 0.300 0.240 MAX 0.210 0.195 0.022 0.070 0.014 1.060 0.325 0.280 MILLIMETERS MIN 0.39 2.93 0.356 1.55 0.204 24.89 0.13 7.62 6.10 MAX 5.33 4.95 0.558 1.77 0.355 26.9 8.25 7.11 NOTES 4 4 8 5 5 6 5 6 7 4 9 Rev. 0 12/93 -C- A2 B B1 C D D1 E eA eC C e C A BS eB NOTES: 1. Controlling Dimensions: INCH. In case of conflict between English and Metric dimensions, the inch dimensions control. 2. Dimensioning and tolerancing per ANSI Y14.5M-1982. 3. Symbols are defined in the “MO Series Symbol List” in Section 2.2 of Publication No. 95. 4. Dimensions A, A1 and L are measured with the package seated in JEDEC seating plane gauge GS-3. 5. D, D1, and E1 dimensions do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.010 inch (0.25mm). 6. E and eA are measured with the leads constrained to be perpendicular to datum -C- . 7. eB and eC are measured at the lead tips with the leads unconstrained. eC must be zero or greater. 8. B1 maximum dimensions do not include dambar protrusions. Dambar protrusions shall not exceed 0.010 inch (0.25mm). 9. N is the maximum number of terminal positions. 10. Corner leads (1, N, N/2 and N/2 + 1) for E8.3, E16.3, E18.3, E28.3, E42.6 will have a B1 dimension of 0.030 - 0.045 inch (0.76 - 1.14mm). E1 e eA eB L N 0.100 BSC 0.300 BSC 0.115 20 0.430 0.150 - 2.54 BSC 7.62 BSC 10.92 3.81 20 2.93 15 FN4878.8 February 27, 2006 ICL3225, ICL3245 Shrink Small Outline Plastic Packages (SSOP) N INDEX AREA E -B1 2 3 0.25 0.010 L GAUGE PLANE H 0.25(0.010) M BM M20.209 (JEDEC MO-150-AE ISSUE B) 20 LEAD SHRINK SMALL OUTLINE PLASTIC PACKAGE INCHES SYMBOL A A1 A2 B C D -C- MILLIMETERS MIN 1.73 0.05 1.68 0.25 0.09 7.07 5.20’ MAX 1.99 0.21 1.78 0.38 0.20’ 7.33 5.38 3 4 9 NOTES MIN 0.068 0.002 0.066 0.010’ 0.004 0.278 0.205 MAX 0.078 0.008’ 0.070’ 0.015 0.008 0.289 0.212 SEATING PLANE -AD A α A1 0.10(0.004) A2 C E e H L N e B 0.25(0.010) M C AM BS 0.026 BSC 0.301 0.025 20 0 deg. 8 deg. 0.311 0.037 0.65 BSC 7.65 0.63 20 0 deg. 8 deg. Rev. 3 11/02 7.90’ 0.95 6 7 α NOTES: 1. Symbols are defined in the “MO Series Symbol List” in Section 2.2 of Publication Number 95. 2. Dimensioning and tolerancing per ANSI Y14.5M-1982. 3. Dimension “D” does not include mold flash, protrusions or gate burrs. Mold flash, protrusion and gate burrs shall not exceed 0.20mm (0.0078 inch) per side. 4. Dimension “E” does not include interlead flash or protrusions. Interlead flash and protrusions shall not exceed 0.20mm (0.0078 inch) per side. 5. The chamfer on the body is optional. If it is not present, a visual index feature must be located within the crosshatched area. 6. “L” is the length of terminal for soldering to a substrate. 7. “N” is the number of terminal positions. 8. Terminal numbers are shown for reference only. 9. Dimension “B” does not include dambar protrusion. Allowable dambar protrusion shall be 0.13mm (0.005 inch) total in excess of “B” dimension at maximum material condition. 10. Controlling dimension: MILLIMETER. Converted inch dimensions are not necessarily exact. 16 FN4878.8 February 27, 2006 ICL3225, ICL3245 Thin Shrink Small Outline Plastic Packages (TSSOP) N INDEX AREA E E1 -B1 2 3 L 0.05(0.002) -AD -CSEATING PLANE A 0.25 0.010 GAUGE PLANE 0.25(0.010) M BM M28.173 28 LEAD THIN SHRINK SMALL OUTLINE PLASTIC PACKAGE INCHES SYMBOL A A1 A2 b c MIN 0.002 0.031 0.0075 0.0035 0.378 0.169 MAX 0.047 0.006 0.051 0.0118 0.0079 0.386 0.177 MILLIMETERS MIN 0.05 0.80 0.19 0.09 9.60 4.30 MAX 1.20 0.15 1.05 0.30 0.20 9.80 4.50 NOTES 9 3 4 6 7 8o Rev. 0 6/98 α A1 0.10(0.004) A2 c D E1 e E L e b 0.10(0.004) M C AM BS 0.026 BSC 0.246 0.0177 28 0o 8o 0.256 0.0295 0.65 BSC 6.25 0.45 28 0o 6.50 0.75 NOTES: 1. These package dimensions are within allowable dimensions of JEDEC MO-153-AE, Issue E. 2. Dimensioning and tolerancing per ANSI Y14.5M-1982. 3. Dimension “D” does not include mold flash, protrusions or gate burrs. Mold flash, protrusion and gate burrs shall not exceed 0.15mm (0.006 inch) per side. 4. Dimension “E1” does not include interlead flash or protrusions. Interlead flash and protrusions shall not exceed 0.15mm (0.006 inch) per side. 5. The chamfer on the body is optional. If it is not present, a visual index feature must be located within the crosshatched area. 6. “L” is the length of terminal for soldering to a substrate. 7. “N” is the number of terminal positions. 8. Terminal numbers are shown for reference only. 9. Dimension “b” does not include dambar protrusion. Allowable dambar protrusion shall be 0.08mm (0.003 inch) total in excess of “b” dimension at maximum material condition. Minimum space between protrusion and adjacent lead is 0.07mm (0.0027 inch). 10. Controlling dimension: MILLIMETER. Converted inch dimensions are not necessarily exact. (Angles in degrees) N α 17 FN4878.8 February 27, 2006 ICL3225, ICL3245 Shrink Small Outline Plastic Packages (SSOP) N INDEX AREA H E -B1 2 3 SEATING PLANE -AD -CA 0.25 0.010 L GAUGE PLANE 0.25(0.010) M BM M28.209 (JEDEC MO-150-AH ISSUE B) 28 LEAD SHRINK SMALL OUTLINE PLASTIC PACKAGE INCHES SYMBOL A A1 A2 B C D E A2 C 0.10(0.004) C AM BS MILLIMETERS MIN 0.05 1.65 0.22 0.09 9.90 5.00 7.40 0.55 28 8° 0° 8° MAX 2.00 1.85 0.38 0.25 10.50 5.60 8.20 0.95 NOTES 9 3 4 6 7 Rev. 2 6/05 MIN 0.002 0.065 0.009 0.004 0.390 0.197 0.292 0.022 28 0° MAX 0.078 0.072 0.014 0.009 0.413 0.220 0.322 0.037 α A1 e B 0.25(0.010) M e H L N 0.026 BSC 0.65 BSC NOTES: 1. Symbols are defined in the “MO Series Symbol List” in Section 2.2 of Publication Number 95. 2. Dimensioning and tolerancing per ANSI Y14.5M-1982. 3. Dimension “D” does not include mold flash, protrusions or gate burrs. Mold flash, protrusion and gate burrs shall not exceed 0.20mm (0.0078 inch) per side. 4. Dimension “E” does not include interlead flash or protrusions. Interlead flash and protrusions shall not exceed 0.20mm (0.0078 inch) per side. 5. The chamfer on the body is optional. If it is not present, a visual index feature must be located within the crosshatched area. 6. “L” is the length of terminal for soldering to a substrate. 7. “N” is the number of terminal positions. 8. Terminal numbers are shown for reference only. 9. Dimension “B” does not include dambar protrusion. Allowable dambar protrusion shall be 0.13mm (0.005 inch) total in excess of “B” dimension at maximum material condition. 10. Controlling dimension: MILLIMETER. Converted inch dimensions are not necessarily exact. α All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9000 quality systems. Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com 18 FN4878.8 February 27, 2006