ISL81334, ISL41334 ® Data Sheet November 21, 2007 ±15kV ESD Protected, 5V, Two Port, Dual Protocol (RS-232/RS-485) Transceivers The ISL81334, ISL41334 are two port interface ICs where each port can be independently configured as a single RS-485, RS-422 transceiver, or as a dual (2 Tx, 2 Rx) RS232 transceiver. With both ports set to the same mode, two RS-485, RS-422 transceivers, or four RS-232 transceivers are available. If either port is in RS-232 mode, the onboard charge pump generates RS-232 compliant ±5V Tx output levels from a single VCC supply as low as 4.5V. Four small 0.1µF capacitors are required for the charge pump. The transceivers are RS-232 compliant, with the Rx inputs handling up to ±25V, and the Tx outputs handling ±12V. In RS-485 mode, the transceivers support both the RS-485 and RS-422 differential communication standards. The receivers feature "full failsafe" operation, so the Rx outputs remain in a high state if the inputs are open or shorted together. The transmitters support up to three data rates, two of which are slew rate limited for problem free communications. The charge pump disables when both ports are in RS-485 mode, thereby saving power, minimizing noise, and eliminating the charge pump capacitors. Both RS-232 and RS-485 modes feature loopback and shutdown functions. Loopback internally connects the Tx outputs to the corresponding Rx input, to facilitate board level self test implementation. The outputs remain connected to the loads during loopback, so connection problems (e.g., shorted connectors or cables) can be detected. Shutdown mode disables the Tx and Rx outputs, disables the charge pumps, and places the IC in a low current (µA) mode. The ISL41334 is a QFN packaged device that includes two additional user selectable, lower speed and edge rate options for EMI sensitive designs, or to allow longer bus lengths. It also features a logic supply pin (VL) that sets the VOH level of logic outputs, and the switching points of logic inputs, to be compatible with another supply voltage in mixed voltage systems. The QFN also adds active low Rx enable pins to increase design flexibility, allowing Tx/Rx direction control, via a single signal per port, by connecting the corresponding DE and RXEN pins together. FN6202.3 Features • ±15kV (HBM) ESD Protected Bus Pins (RS-232 or RS-485) • Two Independent Ports, Each User Selectable for RS-232 (2 Transceivers) or RS-485, RS-422 (1 Transceiver) • Single 5V (10% Tolerance) Supply • Flow-Through Pinouts Simplify Board Layouts • Pb-Free (RoHS Compliant) • Large (2.7V) Differential VOUT for Improved Noise Immunity in RS-485, RS-422 Networks • Full Failsafe (Open/Short) Rx in RS-485, RS-422 Mode • Loopback Mode Facilitates Board Self Test Functions • User Selectable RS-485 Data Rates (ISL41334 Only) - Fast Speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Mbps - Slew Rate Limited. . . . . . . . . . . . . . . . . . . . . . . 460kbps - Slew Rate Limited. . . . . . . . . . . . . . . . . . . . . . . 115kbps • Fast RS-232 Data Rate . . . . . . . . . . . . . . . Up to 650kbps • Low Current Shutdown Mode. . . . . . . . . . . . . . . . . . .42µA • QFN Package Saves Board Space (ISL41334 Only) • Logic Supply Pin (VL) Eases Operation in Mixed Supply Systems (ISL41334 Only) Applications • Gaming Applications (e.g., Slot Machines) • Single Board Computers • Factory Automation • Security Networks • Industrial/Process Control Networks • Level Translators (e.g., RS-232 to RS-422) • Point of Sale Equipment • Dual Channel RS-485 Interfaces For a single port version of these devices, please see the ISL81387, ISL41387 data sheet. TABLE 1. SUMMARY OF FEATURES NO. OF PORTS PACKAGE OPTIONS RS-485 DATA RATE (bps) RS-232 DATA RATE (kbps) VL PIN? ACTIVE H or L Rx ENABLE? LOW POWER SHUTDOWN? ISL81334 2 28 Ld SOIC, 28 Ld SSOP 20M 650 NO NONE YES ISL41334 2 40 Ld QFN (6mmx6mm) 20M, 460k, 115k 650 YES L YES PART NUMBER 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. 2005, 2007. All Rights Reserved. All other trademarks mentioned are the property of their respective owners. ISL81334, ISL41334 Ordering Information PART NUMBER (Note) PART MARKING TEMP. RANGE (°C) PACKAGE (Pb-Free) PKG. DWG. # ISL81334IAZ 81334 IAZ -40 to +85 28 Ld SSOP M28.209 ISL81334IAZ-T* 81334 IAZ -40 to +85 28 Ld SSOP (Tape and Reel) M28.209 ISL81334IBZ ISL81334IBZ -40 to +85 28 Ld SOIC M28.3 ISL81334IBZ-T* ISL81334IBZ -40 to +85 28 Ld SOIC (Tape and Reel) M28.3 ISL41334IRZ 41334 IRZ -40 to +85 40 Ld QFN L40.6x6 ISL41334IRZ-T* 41334 IRZ -40 to +85 40 Ld QFN (Tape and Reel) L40.6x6 *Please refer to TB347 for details on reel specifications. NOTE: These Intersil Pb-free plastic packaged products employ special Pb-free material sets; molding compounds/die attach materials and 100% matte tin plate PLUS ANNEAL - e3 termination finish, which is 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 ISL41334 (40 LD QFN) TOP VIEW Z1 7 VL 23 DZ1/DE1 NC Y1 6 NC 24 RA1 VCC 25 RB1 B1 5 C2- A1 4 C2+ 26 VCC C1+ 27 C2- V+ 3 C1- 28 C2+ C1- 2 NC C1+ 1 NC ISL81334 (28 LD SOIC, 28 LD SSOP) TOP VIEW 40 39 38 37 36 35 34 33 32 31 V+ 1 30 RB1 A1 2 29 RA1 22 DY1 B1 3 28 DZ1/DE1 SEL1 8 21 LB Y1 4 27 DY1 SEL2 9 20 ON/OFF Z1 5 26 LB Z2 10 19 DY2 23 DZ2/DE2 Y2 9 22 RA2 B2 10 21 RB2 2 11 12 13 14 15 16 17 18 19 20 NC 8 V- Z2 15 V- GND 14 RXEN2 24 DY2 RXEN1 7 16 RB2 GND SEL2 A2 13 GND 25 ON/OFF SPB 6 SPA SEL1 17 RA2 NC 18 DZ2/DE2 A2 Y2 11 B2 12 FN6202.3 November 21, 2007 ISL81334, ISL41334 TABLE 2. ISL81334 FUNCTION TABLE INPUTS RECEIVER OUTPUTS DRIVER OUTPUTS SEL1 or 2 ON/OFF DE 1 or 2 RA RB Y Z CHARGE PUMPS (NOTE 1) MODE 0 1 N.A. ON ON ON ON ON RS-232 X 0 X High-Z High-Z High-Z High-Z OFF Shutdown 1 1 0 ON High-Z* High-Z High-Z OFF RS-485 1 1 1 ON High-Z* ON ON OFF RS-485 NOTE: 1. Charge pumps are off iff SEL1 = SEL2 = 1, or if ON/OFF = 0. If ON = 1, and either port is programmed for RS-232 mode, then the charge pumps are on. ISL81334 Truth Tables (FOR EACH PORT) RS-485 TRANSMITTING MODE RS-232 TRANSMITTING MODE INPUTS SEL1 or 2 ON/OFF INPUTS OUTPUTS DY DZ Y Z SEL1 or 2 ON/OFF OUTPUTS DE1 or 2 DY Y Z 1 1 1 0 1 0 0 1 0 0 1 1 1 1 1 1 0 1 0 1 0 1 1 0 1 1 0 X High-Z High-Z 0 1 1 0 0 1 1 0 X X High-Z High-Z 0 1 1 1 0 0 0 0 X X High-Z High-Z RS-485 RECEIVING MODE INPUTS RS-232 RECEIVING MODE SEL1 or 2 ON/OFF INPUTS SEL1 or 2 ON/OFF OUTPUT OUTPUT B-A RA RB* 1 1 ≥ -40mV 1 High-Z A B RA RB 1 1 ≤ -200mV 0 High-Z 0 1 0 0 1 1 1 1 Open or Shorted together 1 High-Z 0 1 0 1 1 0 1 0 X High-Z High-Z 0 1 1 0 0 1 0 1 1 1 0 0 0 1 Open Open 1 1 0 0 X X High-Z High-Z 3 *Internally pulled high through a 40kΩ resistor. FN6202.3 November 21, 2007 ISL81334, ISL41334 TABLE 3. ISL41334 FUNCTION TABLE INPUTS SEL1 or 2 ON/OFF SPA SPB RXEN 1 or 2 DE 1 or 2 RECEIVER OUTPUTS DRIVER OUTPUTS RA RB Y Z CHARGE PUMPS (NOTE 2) DRIVER DATA RATE (Mbps) MODE 0 1 X X 0 N.A. ON ON ON ON ON 0.46 RS-232 0 1 X X 1 N.A. High-Z High-Z ON ON ON 0.46 RS-232 X 0 X X X X High-Z High-Z High-Z High-Z OFF N.A. Shutdown 1 1 X X 0 0 ON High-Z* High-Z High-Z OFF N.A. RS-485 1 1 0 0 0 1 ON High-Z* ON ON OFF 0.46 RS-485 1 1 0 1 0 1 ON High-Z* ON ON OFF 0.115 RS-485 1 1 1 0 0 1 ON High-Z* ON ON OFF 20 RS-485 1 1 1 1 0 1 ON High-Z* ON ON OFF 20 RS-485 1 1 X X 1 0 High-Z High-Z* High-Z High-Z OFF N.A. RS-485 1 1 0 0 1 1 High-Z High-Z* ON ON OFF 0.46 RS-485 1 1 0 1 1 1 High-Z High-Z* ON ON OFF 0.115 RS-485 1 1 1 0 1 1 High-Z High-Z* ON ON OFF 20 RS-485 1 1 1 1 1 1 High-Z High-Z* ON ON OFF 20 RS-485 NOTE: 2. Charge pumps are off iff SEL1 = SEL2 = 1, or if ON/OFF = 0. If ON = 1, and either port is programmed for RS-232 mode, then the charge pumps are on. ISL41334 Truth Tables (FOR EACH PORT) RS-485 TRANSMITTING MODE RS-232 TRANSMITTING MODE INPUTS SEL1 or 2 ON/OFF OUTPUTS DY DZ Y Z SEL1 ON/ DE or 2 OFF 1 or 2 SPA SPB 0 1 0 0 1 1 0 1 0 1 1 0 0 1 1 0 0 1 0 1 1 1 0 0 0 0 X X High-Z High-Z Y Z Mbps 1 0 0 0/1 1/0 0/1 0.46 1 1 1 0 1 0/1 1/0 0/1 0.115 1 1 1 1 X 0/1 1/0 0/1 20 1 1 0 X X X High-Z High-Z N.A. 1 0 X X X X High-Z High-Z N.A. RS-485 RECEIVING MODE A B RA RB 0 1 0 0 0 1 1 0 1 0 0 1 1 0 0 1 0 1 0 0 1 0 1 0 1 1 0 0 0 1 0 Open Open 1 1 0 1 1 X X High-Z High-Z 0 0 X X X High-Z High-Z 4 DY 1 OUTPUT RXEN 1 or 2 SEL1 or 2 ON/OFF DATA RATE 1 RS-232 RECEIVING MODE INPUTS OUTPUTS INPUTS INPUTS OUTPUT SEL1 or 2 ON/OFF RXEN 1 or 2 B-A RA RB * 1 1 0 ≥ -40mV 1 High-Z 1 1 0 ≤ -200mV 0 High-Z 1 1 0 Open or Shorted together 1 High-Z 1 1 1 X High-Z High-Z 1 0 X X High-Z High-Z * Internally pulled high through a 40kΩ resistor. FN6202.3 November 21, 2007 ISL81334, ISL41334 Pin Descriptions PIN MODE FUNCTION GND BOTH Ground connection. LB BOTH Enables loopback mode when low. Internally pulled-high. NC BOTH No Connection. ON/OFF BOTH If either port is in RS-232 mode, a low on ON/OFF disables the charge pumps. In either mode, a low disables all the outputs, and places the device in low power shutdown. Internally pulled-high. ON = 1 for normal operation. RXEN1 RXEN2 BOTH Active low receiver output enable. Rx is enabled when RXEN is low; Rx is high impedance when RXEN is high. Internally pulled low. (QFN only) SEL BOTH Interface Mode Select input. High puts corresponding port in RS-485 Mode, while a low puts it in RS-232 Mode. VCC BOTH System power supply input (5V). VL BOTH Logic-Level Supply. All TTL/CMOS inputs and outputs are powered by this supply. QFN logic input pins that are externally tied high in the application should use the VL supply for the high voltage level. (QFN only) A RS-232 Receiver input with ±15kV ESD protection. A low on A forces RA high; a high on A forces RA low. RS-485 Inverting receiver input with ±15kV ESD protection. B RS-232 Receiver input with ±15kV ESD protection. A low on B forces RB high; a high on B forces RB low. RS-485 Noninverting receiver input with ±15kV ESD protection. DY RS-232 Driver input. A low on DY forces output Y high. Similarly, a high on DY forces output Y low. RS-485 Driver input. A low on DY forces output Y high and output Z low. Similarly, a high on DY forces output Y low and output Z high. DZ RS-232 Driver input. A low on DZ forces output Z high. Similarly, a high on DZ forces output Z low. DE RS-485 Driver output enable. The driver outputs, Y and Z, are enabled by bringing DE high. They are high impedance when DE is low. Internally pulled high when port selected for RS-485 mode. RA RS-232 Receiver output. RS-485 Receiver output: If B > A by at least -40mV, RA is high; If B < A by -200mV or more, RA is low; RA = High if A and B are unconnected (floating) or shorted together (i.e., full fail-safe). RB RS-232 Receiver output. RS-485 Not used. Internally pulled-high, and unaffected by RXEN. Y RS-232 Driver output with ±15kV ESD protection. RS-485 Inverting driver output with ±15kV ESD protection. Z RS-232 Driver output with ±15kV ESD protection. RS-485 Noninverting driver output with ±15kV ESD protection. SP RS-485 Speed control. Internally pulled-high. (QFN only) C1+ RS-232 External capacitor (voltage doubler) is connected to this lead. Not needed if both ports in RS-485 Mode. C1- RS-232 External capacitor (voltage doubler) is connected to this lead. Not needed if both ports in RS-485 Mode. C2+ RS-232 External capacitor (voltage inverter) is connected to this lead. Not needed if both ports in RS-485 Mode. C2- RS-232 External capacitor (voltage inverter) is connected to this lead. Not needed if both ports in RS-485 Mode. V+ RS-232 Internally generated positive RS-232 transmitter supply (+5.5V). C3 not needed if both ports in RS-485 Mode. V- RS-232 Internally generated negative RS-232 transmitter supply (-5.5V). C4 not needed if both ports in RS-485 Mode. 5 FN6202.3 November 21, 2007 ISL81334, ISL41334 Typical Operating Circuit RS-232 MODE WITHOUT LOOPBACK +5V + +5V 0.1µF 1 C1 0.1µF + C2 0.1µF + 2 28 27 C1+ VCC V+ C1C2+ 3 V- 15 C2- 24 R 5kΩ 5 B1 + 0.1µF 26 4 A1 RS-232 MODE WITH LOOPBACK 25 R 5kΩ + C3 0.1µF C4 0.1µF + RA1 RB1 1 C1 0.1µF + C2 0.1µF + 2 28 27 26 C1+ 3 V+ C1C2+ V- 15 C4 0.1µF + 24 R RA1 5kΩ 5 B1 + C3 0.1µF C2- 4 A1 VCC 25 R RB1 5kΩ LB Rx 6 Y1 7 Z1 22 D 23 D LB 8 ON/OFF SEL1 DY1 DZ1 21 6 Y1 7 Z1 VCC 20 LB 8 VCC SEL1 C1 0.1µF C2 0.1µF A1 B1 NOTE: PINOUT FOR SOIC AND SSOP SAME FOR PORT 2. NOTE: PINOUT FOR SOIC AND SSOP SAME FOR PORT 2. Z1 RS-485 MODE WITH LOOPBACK +5V 0.1μF 2 27 C1+ VCC C1C2+ V+ 3 V- 15 C2- 4 24 R 5 + C3 0.1µF C4 0.1µF + C1 0.1µF C2 0.1µF A1 RA1 B1 0.1µF 1 + 2 28 + 27 C1+ 26 VCC V+ C1C2+ 3 V- 15 C2- 4 24 R 5 + C3 0.1µF C4 0.1µF + RA1 LB Rx RB1 6 22 D 7 DY1 25 Y1 Z1 23 DE1 LB 8 ON/OFF SEL1 VCC 20 GND 6 22 VCC D 7 23 21 VCC VCC + 26 25 Y1 VCC 14 28 + GND 20 14 1 + ON/OFF DZ1 21 GND RS-485 MODE WITHOUT LOOPBACK + DY1 23 D GND +5V 22 D DE1 21 VCC VCC RB1 DY1 LB 8 ON/OFF SEL1 GND 20 VCC GND 14 14 NOTE: PINOUT FOR SOIC AND SSOP SAME FOR PORT 2. NOTE: PINOUT FOR SOIC AND SSOP SAME FOR PORT 2. 6 FN6202.3 November 21, 2007 ISL81334, ISL41334 Absolute Maximum Ratings (TA = +25°C) Thermal Information VCC to Ground. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7V VL (QFN Only) . . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to VCC + 0.5V Input Voltages All Except A, B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to 7V Input/Output Voltages A, B (Any Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . -25V to +25V Y, Z (Any Mode, Note 3) . . . . . . . . . . . . . . . . . . . -12.5V to +12.5V RA, RB (non-QFN Package). . . . . . . . . . . . -0.5V to (VCC + 0.5V) RA, RB (QFN Package) . . . . . . . . . . . . . . . . -0.5V to (VL + 0.5V) Output Short Circuit Duration Y, Z, RA, RB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Indefinite ESD Rating . . . . . . . . . . . . . . . . . . . . . . . . . See Specification Table Thermal Resistance θJA (°C/W) 28 Ld SOIC Package (Note 5) . . . . . . . . . . . . . . . . . 65 28 Ld SSOP Package (Note 5) . . . . . . . . . . . . . . . . 60 40 Ld QFN Package (Note 4). . . . . . . . . . . . . . . . . . 32 Maximum Junction Temperature (Plastic Package) . . . . . . +150°C Maximum Storage Temperature Range . . . . . . . . . .-65°C to +150°C Pb-free reflow profile . . . . . . . . . . . . . . . . . . . . . . . . . .see link below http://www.intersil.com/pbfree/Pb-FreeReflow.asp Operating Conditions Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . .-40°C to +85°C CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product reliability and result in failures not covered by warranty. NOTES: 3. One output at a time, IOUT ≤ 100mA for ≤ 10 mins. 4. θJA is measured in free air with the component mounted on a high effective thermal conductivity test board with “direct attach” features. See Tech Brief TB379. 5. θJA is measured with the component mounted on a high effective thermal conductivity test board in free air. See Tech Brief TB379 for details. Electrical Specifications Test Conditions: VCC = 4.5V to 5.5V, C1 - C4 = 0.1µF, VL = VCC (for QFN only); Unless Otherwise Specified. Typicals are at VCC = 5V, TA = +25°C (Note 6). PARAMETER SYMBOL TEMP MIN (°C) (Note 11) TEST CONDITIONS TYP MAX (Note 11) UNITS DC CHARACTERISTICS - RS-485 DRIVER (SEL = VCC) Driver Differential VOUT (no load) VOD1 Driver Differential VOUT (with load) VOD2 Change in Magnitude of Driver Differential VOUT for Complementary Output States Driver Common-Mode VOUT Change in Magnitude of Driver Common-Mode VOUT for Complementary Output States Full - - VCC V R = 50Ω (RS-422) (Figure 1) Full 2.5 3.1 - V R = 27Ω (RS-485) (Figure 1) Full 2.2 2.7 5 V VOD3 RD = 60Ω, R = 375Ω, VCM = -7V to 12V (Figure 1) Full 2 2.7 5 V ΔVOD R = 27Ω or 50Ω (Figure 1) Full - 0.01 0.2 V VOC R = 27Ω or 50Ω (Figure 1) (Note 10) Full - - 3.1 V ΔVOC R = 27Ω or 50Ω (Figure 1) (Note 10) Full - 0.01 0.2 V Full 35 - 250 mA VOUT = 12V Full - - 500 µA VOUT = -7V Full -200 - - µA Driver Short-Circuit Current, VOUT = High or Low IOS -7V ≤ (VY or VZ) ≤ 12V (Note 8) Driver Three-State Output Leakage Current (Y, Z) IOZ Outputs Disabled, VCC = 0V or 5.5V DC CHARACTERISTICS - RS-232 DRIVER (SEL = GND) Driver Output Voltage Swing VO All TOUTS Loaded with 3kΩ to Ground Full ±5.0 +6/-7 - V Driver Output Short-Circuit Current IOS VOUT = 0V Full -60 25/-35 60 mA DC CHARACTERISTICS - LOGIC PINS (i.e., DRIVER AND CONTROL INPUT PINS) Input High Voltage 7 VIH1 VL = VCC if QFN Full 2 1.6 - V VIH2 VL = 3.3V (QFN Only) Full 2 1.2 - V VIH3 VL = 2.5V (QFN Only) Full 1.5 1 - V FN6202.3 November 21, 2007 ISL81334, ISL41334 Electrical Specifications Test Conditions: VCC = 4.5V to 5.5V, C1 - C4 = 0.1µF, VL = VCC (for QFN only); Unless Otherwise Specified. Typicals are at VCC = 5V, TA = +25°C (Note 6). (Continued) PARAMETER SYMBOL Input Low Voltage Input Current TEMP MIN (°C) (Note 11) TEST CONDITIONS TYP MAX (Note 11) UNITS VIL1 VL = VCC if QFN Full - 1.4 0.8 V VIL2 VL = 3.3V (QFN Only) Full - 1 0.7 V VIL3 VL = 2.5V (QFN Only) Full - - 0.5 V IIN1 Pins Without Pull-ups or Pull-downs Full -2 - 2 µA IIN2 LB, ON/OFF, DE, SP (QFN), RXEN (QFN) Full -25 - 25 µA -7V ≤ VCM ≤ 12V, Full Failsafe Full -0.2 - -0.04 V VCM = 0V 25 - 35 - mV VIN = 12V Full - - 0.8 mA VIN = -7V Full -0.64 - - mA Full 15 - - kΩ DC CHARACTERISTICS - RS-485 RECEIVER INPUTS (SEL = VCC) Receiver Differential Threshold Voltage VTH ΔVTH Receiver Input Hysteresis Receiver Input Current (A, B) IIN Receiver Input Resistance RIN VCC = 0V or 4.5 to 5.5V -7V ≤ VCM ≤ 12V, VCC = 0 (Note 9) or 4.5V ≤ VCC ≤ 5.5V DC CHARACTERISTICS - RS-232 RECEIVER INPUTS (SEL = GND) Receiver Input Voltage Range VIN Full -25 - 25 V Receiver Input Threshold VIL Full - 1.4 0.8 V VIH Full 2.4 1.9 - V Receiver Input Hysteresis ΔVTH 25 - 0.5 - V Receiver Input Resistance RIN Full 3 5 7 kΩ VIN = ±15V, VCC Powered Up (Note 9) DC CHARACTERISTICS - RECEIVER OUTPUTS (485 OR 232 MODE) Receiver Output High Voltage VOH1 IO = -2mA (VL = VCC if QFN) Full 3.5 4.6 - V VOH2 IO = -650µA, VL = 3V (QFN Only) Full 2.6 2.9 - V VOH3 IO = -500µA, VL = 2.5V (QFN Only) Full 2 2.4 - V Receiver Output Low Voltage VOL IO = 3mA Full - 0.1 0.4 V Receiver Short-Circuit Current IOSR 0V ≤ VO ≤ VCC Full 7 - 85 mA Receiver Three-State Output Current IOZR Output Disabled, 0V ≤ VO ≤ VCC (or VL for QFN) Full - - ±10 µA Unused Receiver (RB) Pull-Up Resistance ROBZ ON/OFF = VCC, SELX = VCC (RS-485 Mode) 25 - 40 - kΩ ICC232 SEL1 or SEL2 = GND, LB = ON/OFF = VCC Full - 3.7 7 mA ICC485 SEL 1 and 2 = LB = DE = ON/OFF = VCC Full - 1.6 5 mA ISHDN232 ON/OFF = SELX = GND, LB = VCC, (SPX = VCC if QFN) Full - 25 50 µA ISHDN485 ON/OFF = DEX = GND, SELX = LB = VCC, (SPX = GND if QFN) SOIC/SSOP Full - 42 80 µA QFN Full - 80 160 µA POWER SUPPLY CHARACTERISTICS No-Load Supply Current (Note 7) Shutdown Supply Current ESD CHARACTERISTICS Bus Pins (A, B, Y, Z) Any Mode Human Body Model 25 - 15 - kV All Other Pins Human Body Model 25 - 4 - kV 8 FN6202.3 November 21, 2007 ISL81334, ISL41334 Electrical Specifications Test Conditions: VCC = 4.5V to 5.5V, C1 - C4 = 0.1µF, VL = VCC (for QFN only); Unless Otherwise Specified. Typicals are at VCC = 5V, TA = +25°C (Note 6). (Continued) PARAMETER SYMBOL TEMP MIN (°C) (Note 11) TEST CONDITIONS TYP MAX (Note 11) UNITS RS-232 DRIVER AND RECEIVER SWITCHING CHARACTERISTICS (SEL = GND, ALL VERSIONS AND SPEEDS) Driver Output Transition Region Slew Rate SR Driver Output Transition Time tr, tf Driver Propagation Delay tDPHL CL ≥ 15pF Full - 18 30 V/µs CL ≤ 2500pF Full 4 12 - V/µs RL = 3kΩ, CL = 2500pF, 10% to 90% Full 0.22 1.2 3.1 µs RL = 3kΩ, CL = 1000pF (Figure 6) Full - 1 2 µs Full - 1.2 2 µs RL = 3kΩ, Measured From 3V to -3V or -3V to 3V tDPLH Driver Propagation Delay Skew tDSKEW tDPHL - tDPLH (Figure 6) Full - 240 400 ns Driver Enable Time from Shutdown tDENSD VOUT = ±3.0V 25 - 20 - µs Driver Maximum Data Rate DRD RL = 3kΩ, CL = 1000pF, One Transmitter Switching per port Full 460 650 - kbps Receiver Propagation Delay tRPHL CL = 15pF (Figure 7) Full - 50 120 ns Full - 40 120 ns tRPHL - tRPLH (Figure 7) Full - 10 40 ns CL = 15pF Full 0.46 2 - Mbps tRPLH Receiver Propagation Delay Skew tRSKEW Receiver Maximum Data Rate DRR RS-485 DRIVER SWITCHING CHARACTERISTICS (FAST DATA RATE (20Mbps), SEL = VCC, ALL VERSIONS (SPA = VCC if QFN)) Driver Differential Input to Output Delay tDLH, tDHL RDIFF = 54Ω, CL = 100pF (Figure 2) Full 15 30 50 ns Driver Output Skew tSKEW RDIFF = 54Ω, CL = 100pF (Figure 2) Full - 3 10 ns tR, tF RDIFF = 54Ω, CL = 100pF (Figure 2) Full 3 11 20 ns Driver Differential Rise or Fall Time Driver Enable to Output Low tZL CL = 100pF, SW = VCC (Figure 3) Full - 27 60 ns Driver Enable to Output High tZH CL = 100pF, SW = GND (Figure 3) Full - 24 60 ns Driver Disable from Output Low tLZ CL = 15pF, SW = VCC (Figure 3) Full - 31 60 ns Driver Disable from Output High tHZ CL = 15pF, SW = GND (Figure 3) Full - 24 60 ns Driver Enable from Shutdown to Output Low tZL(SHDN) RL = 500Ω, CL = 100pF, SW = VCC (Figure 3) Full - 65 250 ns Driver Enable from Shutdown to Output High tZH(SHDN) RL = 500Ω, CL = 100pF, SW = GND (Figure 3) Full - 152 250 ns Full - 30 - Mbps Driver Maximum Data Rate fMAX RDIFF = 54Ω, CL = 100pF (Figure 2) RS-485 DRIVER SWITCHING CHARACTERISTICS (MEDIUM DATA RATE (460kbps, QFN ONLY), SEL = VCC, SPA = SPB = GND) Driver Differential Input to Output Delay tDLH, tDHL RDIFF = 54Ω, CL = 100pF (Figure 2) Full 200 490 1000 ns Driver Output Skew tSKEW RDIFF = 54Ω, CL = 100pF (Figure 2) Full - 110 400 ns tR, tF RDIFF = 54Ω, CL = 100pF (Figure 2) Full 300 600 1100 ns Driver Differential Rise or Fall Time Driver Enable to Output Low tZL CL = 100pF, SW = VCC (Figure 3) Full - 30 300 ns Driver Enable to Output High tZH CL = 100pF, SW = GND (Figure 3) Full - 128 300 ns Driver Disable from Output Low tLZ CL = 15pF, SW = VCC (Figure 3) Full - 31 60 ns Driver Disable from Output High tHZ CL = 15pF, SW = GND (Figure 3) Full - 24 60 ns Driver Enable from Shutdown to Output Low tZL(SHDN) RL = 500Ω, CL = 100pF, SW = VCC (Figure 3) Full - 65 500 ns Driver Enable from Shutdown to Output High tZH(SHDN) RL = 500Ω, CL = 100pF, SW = GND (Figure 3) Full - 255 500 ns 9 FN6202.3 November 21, 2007 ISL81334, ISL41334 Electrical Specifications Test Conditions: VCC = 4.5V to 5.5V, C1 - C4 = 0.1µF, VL = VCC (for QFN only); Unless Otherwise Specified. Typicals are at VCC = 5V, TA = +25°C (Note 6). (Continued) PARAMETER SYMBOL Driver Maximum Data Rate fMAX TEMP MIN (°C) (Note 11) TEST CONDITIONS RDIFF = 54Ω, CL = 100pF (Figure 2) Full - TYP 2000 MAX (Note 11) UNITS - kbps RS-485 DRIVER SWITCHING CHARACTERISTICS (SLOW DATA RATE (115kbps, QFN ONLY), SEL = VCC, SPA = GND, SPB = VCC) Driver Differential Input to Output Delay tDLH, tDHL RDIFF = 54Ω, CL = 100pF (Figure 2) Full 800 1500 2500 ns Driver Output Skew tSKEW RDIFF = 54Ω, CL = 100pF (Figure 2) Full - 350 1250 ns tR, tF RDIFF = 54Ω, CL = 100pF (Figure 2) Full 1000 2000 3100 ns Driver Differential Rise or Fall Time Driver Enable to Output Low tZL CL = 100pF, SW = VCC (Figure 3) Full - 32 600 ns Driver Enable to Output High tZH CL = 100pF, SW = GND (Figure 3) Full - 300 600 ns Driver Disable from Output Low tLZ CL = 15pF, SW = VCC (Figure 3) Full - 31 60 ns Driver Disable from Output High tHZ CL = 15pF, SW = GND (Figure 3) Full - 24 60 ns Driver Enable from Shutdown to Output Low tZL(SHDN) RL = 500Ω, CL = 100pF, SW = VCC (Figure 3) Full - 65 800 ns Driver Enable from Shutdown to Output High tZH(SHDN) RL = 500Ω, CL = 100pF, SW = GND (Figure 3) Full - 420 800 ns Full - 800 - kbps Full 20 50 90 ns Full - 0.1 10 ns Full - 40 - Mbps Driver Maximum Data Rate fMAX RDIFF = 54Ω, CL = 100pF (Figure 2) RS-485 RECEIVER SWITCHING CHARACTERISTICS (SEL = VCC, ALL VERSIONS AND SPEEDS) Receiver Input to Output Delay tPLH, tPHL (Figure 4) Receiver Skew | tPLH - tPHL | tSKEW Receiver Maximum Data Rate fMAX (Figure 4) RECEIVER ENABLE/DISABLE CHARACTERISTICS (ALL MODES AND SPEEDS) Receiver Enable to Output Low tZL QFN Only, CL = 15pF, SW = VCC (Figure 5) Full - 22 60 ns Receiver Enable to Output High tZH QFN Only, CL = 15pF, SW = GND (Figure 5) Full - 23 60 ns Receiver Disable from Output Low tLZ QFN Only, CL = 15pF, SW = VCC (Figure 5) Full - 24 60 ns Receiver Disable from Output High tHZ QFN Only, CL = 15pF, SW = GND (Figure 5) Full - 25 60 ns Receiver Enable from Shutdown to Output Low tZLSHDN CL = 15pF, SW = VCC (Figure 5) RS-485 Mode Full - 260 700 ns RS-232 Mode 25 - 35 - ns Receiver Enable from Shutdown to Output High tZHSHDN RS-485 Mode Full - 260 700 ns RS-232 Mode 25 - 25 - ns CL = 15pF, SW = GND (Figure 5) NOTES: 6. All currents into device pins are positive; all currents out of device pins are negative. All voltages are referenced to device ground unless otherwise specified. 7. Supply current specification is valid for loaded drivers when DE = 0V (RS-485 mode only). 8. Applies to peak current. See “Typical Performance Curves” starting on page 19 for more information. 9. RIN defaults to RS-485 mode (>15kΩ) when the device is unpowered (VCC = 0V), or in SHDN, regardless of the state of the SEL inputs. 10. VCC ≤ 5.25V. 11. Parts are 100% tested at +25°C. Over-temperature limits established by characterization and are not production tested. 10 FN6202.3 November 21, 2007 ISL81334, ISL41334 Test Circuits and Waveforms R VCC DE DY Y RD D VOD Z VOC R FIGURE 1. RS-485 DRIVER VOD AND VOC TEST CIRCUIT 3V DY 1.5V 1.5V 0V tPLH tPHL VOH 50% OUT (Z) 50% VOL tPHL VCC CL = 100pF DE DY tPLH VOH OUT (Y) 50% 50% VOL Y tDLH RDIFF D Z CL = 100pF 90% DIFF OUT (Z - Y) 10% SIGNAL GENERATOR tDHL 0V 0V +VOD 90% 10% tR -VOD tF SKEW = |tPLH (Y or Z) - tPHL (Z or Y)| FIGURE 2A. TEST CIRCUIT FIGURE 2B. MEASUREMENT POINTS FIGURE 2. RS-485 DRIVER PROPAGATION DELAY AND DIFFERENTIAL TRANSITION TIMES 11 FN6202.3 November 21, 2007 ISL81334, ISL41334 Test Circuits and Waveforms (Continued) DE Y DY 500Ω VCC D SIGNAL GENERATOR SW Z GND ENABLED DE (ON/OFF FOR SHDN) 3V 1.5V 1.5V 0V CL tZH tZH(SHDN) OUTPUT HIGH OUT (Y, Z) FOR SHDN TESTS, SWITCH ON/OFF RATHER THAN DE PARAMETER ON/DE OUTPUT DY SW tHZ 1/- Y/Z 0/1 GND 15 tLZ 1/- Y/Z 1/0 VCC 15 tZH 1/- Y/Z 0/1 GND 100 tZL 1/- Y/Z 1/0 VCC 100 tZH(SHDN) -/1 Y/Z 0/1 GND 100 tZL(SHDN) -/1 Y/Z 1/0 VCC 100 tHZ VOH - 0.5V VOH 2.3V 0V CL (pF) tZL tZL(SHDN) tLZ VCC OUT (Y, Z) 2.3V OUTPUT LOW VOL + 0.5V V OL FIGURE 3B. MEASUREMENT POINTS FIGURE 3A. TEST CIRCUIT FIGURE 3. RS-485 DRIVER ENABLE AND DISABLE TIMES +1.5V RXEN (QFN ONLY) 15pF A 0V B RA R B 0V 0V -1.5V tPLH tPHL VCC RA SIGNAL GENERATOR 1.5V 1.5V 0V FIGURE 4B. MEASUREMENT POINTS FIGURE 4A. TEST CIRCUIT FIGURE 4. RS-485 RECEIVER PROPAGATION DELAY RXEN (QFN ONLY) A R SIGNAL GENERATOR 1kΩ RA VCC SW B ON/OFF (FOR SHDN TESTS) 0V ENABLED GND RXEN (QFN ONLY) 15pF 3V 1.5V 1.5V 3V 1.5V 0V tZH tZH(SHDN) FOR SHDN TESTS, SWITCH ON/OFF RATHER THAN RXEN PARAMETER ON/RXEN B SW tHZ (QFN Only) 1/- +1.5V GND RA tHZ VOH - 0.5V VOH 1.5V 0V tLZ (QFN Only) 1/- -1.5V VCC tZH (QFN Only) 1/- +1.5V GND tZL tZL(SHDN) tZL (QFN Only) 1/- -1.5V VCC RA tZH(SHDN) -/0 +1.5V GND tZL(SHDN) -/0 -1.5V VCC FIGURE 5A. TEST CIRCUIT OUTPUT HIGH tLZ VCC 1.5V OUTPUT LOW VOL + 0.5V V OL FIGURE 5B. MEASUREMENT POINTS FIGURE 5. RS-485 RECEIVER ENABLE AND DISABLE TIMES 12 FN6202.3 November 21, 2007 ISL81334, ISL41334 Test Circuits and Waveforms (Continued) 3V DY,Z DY,Z 1.5V CL Y, Z D 1.5V 0V tDPHL RL SIGNAL GENERATOR tDPLH VO+ OUT (Y,Z) 0V 0V VO- SKEW = |tDPHL - tDPLH| FIGURE 6A. TEST CIRCUIT FIGURE 6B. MEASUREMENT POINTS FIGURE 6. RS-232 DRIVER PROPAGATION DELAY AND TRANSITION TIMES 3V RXEN (QFN ONLY) A, B RA, RB R A, B 1.3V 1.7V 0V CL = 15pF tRPLH tRPHL 2.4V RA, RB SIGNAL GENERATOR 0.8V VOL SKEW = |tRPHL - tRPLH| FIGURE 7A. TEST CIRCUIT VOH FIGURE 7B. MEASUREMENT POINTS FIGURE 7. RS-232 RECEIVER PROPAGATION DELAY AND TRANSITION TIMES Typical Application +5V + 0.1µF RS-232 to RS-485 Converter The ISL81334, ISL41334 are ideal for implementing a single IC 2-wire (Tx Data, Rx Data) protocol converter, because each port can be programmed for a different protocol. Figure 8 illustrates the simple connections to create a single transceiver RS-232 to RS-485 converter. Depending on the RS-232 data rate, using an RS-422 bus as an RS-232 “extension cord” can extend the transmission distance up to 4000’ (1220m). A similar circuit on the other end of the cable completes the conversion to/from RS-232. Detailed Description Each of the two ISL81334, ISL41334 ports supports dual protocols: RS-485/422, and RS-232. RS-485 and RS-422 are differential (balanced) data transmission standards for use in high speed (up to 20Mbps) networks, or long haul and noisy environments. The differential signaling, coupled with RS-485’s requirement for extended common mode range (CMR) of +12V to -7V make these transceivers extremely tolerant of ground potential differences, as well as voltages induced in the cable by external fields. Both of these effects are real concerns when communicating over the RS-485, RS-422 maximum distance of 4000’ (1220m). It is important to note that the ISL81334, ISL41334 don’t follow the RS-485 convention whereby the inverting I/O is labeled “B/Z”, and the noninverting I/O is “A/Y”. Thus, in the application diagrams below the 1334 A/Y (B/Z) pins connect to the B/Z (A/Y) pins of the generic RS-485, RS-422 ICs. 13 C1 0.1µF 1 + C1+ C2 0.1µF 2 C128 C2+ + 27 C2- NC 4 A1 26 VCC V+ 3 V- 15 R RA1 24 +C3 0.1µF C4 0.1µF + NC 5kΩ TxD RS-232 IN 5 B1 R RB1 25 5kΩ 6 Y1 NC RxD RS-232 OUT D 7 Z1 8 VCC 9 D RS-485 OUT DZ1 23 SEL1 ON/OFF SEL2 13 A2 RS-485 IN DY1 22 12 B2 11 Y2 10 Z2 R D 20 VCC RA2 17 DY2 19 DE2 18 VCC GND 14 NOTE: PINOUT FOR SOIC AND SSOP FIGURE 8. SINGLE IC RS-232 TO RS-485 CONVERTER FN6202.3 November 21, 2007 ISL81334, ISL41334 Protocol selection is handled via a logic pin (SELX) for each port. RS-422 is typically a point-to-point (one driver talking to one receiver on a bus), or a point-to-multipoint (multidrop) standard that allows only one driver and up to 10 receivers on each bus. Because of the one driver per bus limitation, RS-422 networks use a two bus, full duplex structure for bidirectional communication, and the Rx inputs and Tx outputs (no tri-state required) connect to different busses, as shown in Figure 10. . ISL81334, ISL41334 Advantages These dual protocol ICs offer many parametric improvements versus those offered on competing dual protocol devices. Some of the major improvements are: • 15kV Bus Pin ESD - Eases board level requirements Conversely, RS-485 is a true multipoint standard, which allows up to 32 devices (any combination of drivers- must be tri-statable - and receivers) on each bus. Now bidirectional communication takes place on a single bus, so the Rx inputs and Tx outputs of a port connect to the same bus lines, as shown in Figure 9. Each port set to RS-485 /422 mode includes one Rx and one Tx. • 2.7V Diff VOUT - Better Noise immunity and/or distance • Full Failsafe RS-485 Rx - Eliminates bus biasing • Selectable RS-485 Data Rate - Up to 20Mbps, or slewrate limited for low EMI and fewer termination issues • High RS-232 Data Rate - >460kbps • Lower Tx and Rx Skews - Wider, consistent bit widths RS-232 is a point-to-point, singled ended (signal voltages referenced to GND) communication protocol targeting fairly short (<150’, 46m) and low data rate (<1Mbps) applications. Each port contains two transceivers (2 Tx and 2 Rx) in RS-232 mode. • Lower ICC - Max ICC is 2x to 4x lower than competition • Flow-Thru Pinouts - Tx, Rx bus pins on one side/logic pins on the other, for easy routing to connector/UART • Smaller (SSOP and QFN) and Pb-free Packaging. + GENERIC 1/2 DUPLEX 485 XCVR +5V + VCC DI +5V + 0.1μF VCC GND VCC RO R B/Z RE Tx/Rx A/Y DE DY GENERIC 1/2 DUPLEX 485 XCVR +5V D A RXEN * DE R 0.1μF B R RE 0.1μF ISL81334, ISL41334 RA RO D DE B/Z Y D A/Y Z GND RT RT DI GND * QFN ONLY FIGURE 9. TYPICAL HALF DUPLEX RS-485 NETWORK + GENERIC 422 Rx (SLAVE) +5V R 0.1μF +5V VCC GND B 0.1μF D VCC RT Z A Y B RO R Z RT A R + A VCC DE RA GENERIC FULL DUPLEX 422 XCVR (SLAVE) + ISL81334, ISL41334 (MASTER) DY RE 0.1μF +5V 1kΩ OR NC RO B D Y DI GND GND FIGURE 10. TYPICAL RS-422 NETWORK 14 FN6202.3 November 21, 2007 ISL81334, ISL41334 RS-232 Mode both ports in RS-485 mode (e.g., a dedicated dual channel RS-485 interface), then the charge pump capacitors aren’t even required. RX FEATURES RS-232 receivers invert and convert RS-232 input levels (±3V to ±25V) to the standard TTL/CMOS levels required by a UART, ASIC, or µcontroller serial port. Receivers are designed to operate at faster data rates than the drivers, and they feature very low skews (10ns) so the receivers contribute negligibly to bit width distortion. Inputs include the standards required 3kΩ to 7kΩ pulldown resistor, so unused inputs may be left unconnected. Rx inputs also have built-in hysteresis to increase noise immunity, and to decrease erroneous triggering due to slowly transitioning input signals. Rx outputs are short circuit protected, and are only tri-statable when the entire IC is shutdown via the ON/OFF pin, or via the active low RXEN pin available on the QFN package option (see “ISL41334 (QFN Package) Special Features” on page 17 for more details). TX FEATURES RS-232 drivers invert and convert the standard TTL/CMOS levels from a UART, or µcontroller serial port to RS-232 compliant levels (±5V minimum). The Tx delivers these compliant output levels even at data rates of 650kbps, and with loads of 1000pF. The drivers are designed for low skew (typically 12% of the 500kbps bit width), and are compliant to the RS-232 slew rate specification (4V/µs to 30V/µs) for a wide range of load capacitances. Tx inputs float if left unconnected, and may cause ICC increases. For the best results, connect unused inputs to GND. Tx outputs are short circuit protected, and incorporate a thermal SHDN feature to protect the IC in situations of severe power dissipation. See the RS-485 section for more details. Drivers tri-state only in SHDN, or when the 5V power supply is off. The SHDN function is useful for tri-stating the outputs if both ports will always be tri-stated together (e.g., used as a four transceiver RS-232 port), and if it is acceptable for the Rx to be disabled as well. A single port Tx disable can be accomplished by switching the port to RS-485 mode, and then using the corresponding DE pin to tri-state the drivers. Of course, the Rx is now an RS-485 Rx, so this option is feasible only if the Rx aren’t needed when the Tx are disabled. CHARGE PUMPS The on-chip charge pumps create the RS-232 transmitter power supplies (typically +6/-7V) from a single supply as low as 4.5V, and are enabled only if either port is configured for RS-232 operation. The efficient design requires only four small 0.1µF capacitors for the voltage doubler and inverter functions. By operating discontinuously (i.e., turning off as soon as V+ and V- pump up to the nominal values), the charge pump contribution to RS-232 mode ICC is reduced significantly. Unlike competing devices that require the charge pump in RS-485 mode, disabling the charge pump saves power, and minimizes noise. If the application keeps 15 DATA RATES AND CABLING Drivers operate at data rates of up to 650kbps, and are guaranteed for data rates of up to 460kbps. The charge pumps and drivers are designed such that one driver in each port can be operated at the rated load, and at 460kbps (see Figure 34). Figure 34 also shows that drivers can easily drive several thousands of picofarads at data rates up to 250kbps, while still delivering compliant ±5V output levels. Receivers operate at data rates up to 2Mbps. They are designed for a higher data rate to facilitate faster factory downloading of software into the final product, thereby improving the user’s manufacturing throughput. Figures 37 and 38 illustrate driver and receiver waveforms at 250kbps, and 500kbps, respectively. For these graphs, one driver of each port drives the specified capacitive load, and a receiver in the port. RS-232 doesn’t require anything special for cabling; just a single bus wire per transmitter and receiver, and another wire for GND. So an ISL81334, ISL41334 RS-232 port uses a five conductor cable for interconnection. Bus terminations are not required, nor allowed, by the RS-232 standard. RS-485 Mode RX FEATURES RS-485 receivers convert differential input signals as small as 200mV, as required by the RS-485 and RS-422 standards, to TTL/CMOS output levels. The differential Rx provides maximum sensitivity, noise immunity, and common mode rejection. Per the RS-485 standard, receiver inputs function with common mode voltages as great as ±7V outside the power supplies (i.e., +12V and -7V), making them ideal for long networks where induced voltages are a realistic concern. Each RS-485, RS-422 port includes a single receiver (RA), and the unused Rx output (RB) is disabled, but pulled high by an internal current source. The internal current source turns off in SHDN. Worst case receiver input currents are 20% lower than the 1 “unit load” (1mA) RS-485 limit, which translates to a 15kΩ minimum input resistance. These receivers include a “full fail-safe” function that guarantees a high level receiver output if the receiver inputs are unconnected (floating), shorted together, or if the bus is terminated but undriven (i.e., differential voltage collapses to near zero due to termination). Failsafe with shorted, or terminated and undriven inputs is accomplished by setting the Rx upper switching point at -40mV, thereby ensuring that the Rx recognizes a 0V differential as a high level. All the Rx outputs are short circuit protected, and are tri-state when the IC is forced into SHDN, but ISL81334 (SOIC and FN6202.3 November 21, 2007 ISL81334, ISL41334 SSOP) receiver outputs are not independently tri-statable. ISL41334 (QFN) receiver outputs are tri-statable via an active low RXEN input for each port (see “ISL41334 (QFN Package) Special Features” on page 17 for more details). TX FEATURES The RS-485, RS-422 driver is a differential output device that delivers at least 2.2V across a 54Ω load (RS-485), and at least 2.5V across a 100Ω load (RS-422). Both levels significantly exceed the standards requirements, and these exceptional output voltages increase system noise immunity, and/or allow for transmission over longer distances. The drivers feature low propagation delay skew to maximize bit widths, and to minimize EMI. To allow multiple drivers on a bus, the RS-485 spec requires that drivers survive worst case bus contentions undamaged. The ISL81334, ISL41334 drivers meet this requirement via driver output short circuit current limits, and on-chip thermal shutdown circuitry. The output stages incorporate current limiting circuitry that ensures that the output current never exceeds the RS-485 specification, even at the common mode voltage range extremes. In the event of a major short circuit condition, devices also include a thermal shutdown feature that disables the drivers whenever the die temperature becomes excessive. This eliminates the power dissipation, allowing the die to cool. The drivers automatically re-enable after the die temperature drops about 15°. If the contention persists, the thermal shutdown/re-enable cycle repeats until the fault is cleared. Receivers stay operational during thermal shutdown. RS-485 multi-driver operation also requires drivers to include tri-state functionality, so each port has a DE pin to control this function. If the driver is used in an RS-422 network, such that driver tri-state isn’t required, then the DE pin can be left unconnected and an internal pull-up keeps it in the enabled state. Drivers are also tri-stated when the IC is in SHDN, or when the 5V power supply is off. SPEED OPTIONS The ISL81334 (SOIC, SSOP) has fixed, high slew rate driver outputs optimized for 20Mbps data rates. The ISL41334 (QFN) offers three user selectable data rate options: “Fast” for high slew rate and 20Mbps; “Medium” with slew rate limiting set for 460kbps; “Slow” with even more slew rate limiting for 115kbps operation. See “Data Rate, Cables, and Terminations” on page 16 and “RS-485 Slew Rate Limited Data Rates” on page 19 for more information. Receiver performance is the same for all three speed options. DATA RATE, CABLES, AND TERMINATIONS RS-485, RS-422 are intended for network lengths up to 4000’ (1220m), but the maximum system data rate decreases as the transmission length increases. Devices operating at the maximum data rate of 20Mbps are limited to 16 lengths of 20’ to 30’ (6m to 9m), while devices operating at or below 115kbps can operate at the maximum length of 4000’ (1220m). Higher data rates require faster edges, so both the ISL81334, ISL41334 versions offer an edge rate capable of 20Mbps data rates. The ISL41334 also offers two slew rate limited edge rates to minimize problems at slower data rates. Nevertheless, for the best jitter performance when driving long cables, the faster speed settings may be preferable, even at low data rates. See “RS-485 Slew Rate Limited Data Rates” on page 19 for details. Twisted pair is the cable of choice for RS-485, RS-422 networks. Twisted pair cables tend to pick up noise and other electromagnetically induced voltages as common mode signals, which are effectively rejected by the differential receivers in these ICs. The preferred cable connection technique is “daisy-chaining”, where the cable runs from the connector of one device directly to the connector of the next device, such that cable stub lengths are negligible. A “backbone” structure, where stubs run from the main backbone cable to each device’s connector, is the next best choice, but care must be taken to ensure that each stub is electrically “short”. See Table 4 for recommended maximum stub lengths for each speed option. TABLE 4. RECOMMENDED STUB LENGTHS SPEED OPTION MAXIMUM STUB LENGTH ft (m) SLOW 350 to 500 (107 to 152) MED 100 to 150 (30.5 to 46) FAST 1 to 3 (0.3 to 0.9) Proper termination is imperative to minimize reflections when using the 20Mbps speed option. Short networks using the medium and slow speed options need not be terminated, but terminations are recommended unless power dissipation is an overriding concern. Note that the RS-485 specification allows a maximum of two terminations on a network, otherwise the Tx output voltage may not meet the required VOD. In point-to-point, or point-to-multipoint (RS-422) networks, the main cable should be terminated in its characteristic impedance (typically 120Ω) at the end farthest from the driver. In multi-receiver applications, stubs connecting receivers to the main cable should be kept as short as possible, but definitely shorter than the limits shown in Table 4. Multipoint (RS-485) systems require that the main cable be terminated in its characteristic impedance at both ends. Again, keep stubs connecting a transceiver to the main cable as short as possible, and refer to Table 4. Avoid “star”, and other configurations, where there are many “ends” which would require more than the two allowed terminations to prevent reflections. FN6202.3 November 21, 2007 ISL81334, ISL41334 High ESD All pins on the ISL81334, ISL41334 include ESD protection structures rated at ±4kV (HBM), which is good enough to survive ESD events commonly seen during manufacturing. But the bus pins (Tx outputs and Rx inputs) are particularly vulnerable to ESD events because they connect to an exposed port on the exterior of the finished product. Simply touching the port pins, or connecting a cable, can destroy an unprotected port. ISL81334, ISL41334 bus pins are fitted with advanced structures that deliver ESD protection in excess of ±15kV (HBM), without interfering with any signal in the RS-485 or the RS-232 range. This high level of protection may eliminate the need for board level protection, or at the very least will increase the robustness of any board level scheme. Small Packages All but 5µA of SHDN ICC current is due to control input (ON, LB, SP, DE) pull-up resistors (~20µA/resistor), so SHDN ICC varies depending on the ISL81334, ISL41334 configuration. The specification tables indicate the worst case values, but careful selection of the configuration yields lower currents. For example, in RS-232 mode the SP pins aren’t used, so if both ports are configured for RS-232, floating or tying the SP pins high minimizes SHDN ICC. Likewise in RS-485 mode, the drivers are disabled in SHDN, so driving the DE pins high during this time also reduces ICC. On the ISL41334, the SHDN ICC increases as VL decreases. VL powers the input stage and sets its VOH at VL rather than VCC. VCC powers the second stage, but the second stage input isn’t driven to the rail, so some ICC current flows. See Figure 21 for details. Many competing dual protocol ICs are available only in monstrously large 24 to 28 Ld SOIC packages. The ISL81334’s 28 Ld SSOP is 50% smaller than even a 24 Ld SOIC, and the ISL41334’s tiny 6mmx6mm QFN is 80% smaller than a 28 Ld SOIC. When enabling from SHDN in RS-232 mode, allow at least 20µs for the charge pumps to stabilize before transmitting data. The charge pumps aren’t used in RS-485 mode, so the transceiver is ready to send or receive data in less than 1µs, which is much faster than competing devices that require the charge pump for all modes of operation. Flow Through Pinouts Internal Loopback Mode Even the ISL81334, ISL41334 pinouts are features, in that the “flow-through” design simplifies board layout. Having the bus pins all on one side of the package for easy routing to a cable connector, and the Rx outputs and Tx inputs on the other side for easy connection to a UART, avoids costly and problematic crossovers. Figure 11 illustrates the flow-through nature of the pinout. Driving the LB pin low places both ports in the loopback mode, a mode that facilitates implementing board level self test functions. In loopback, internal switches disconnect the Rx inputs from the Rx outputs, and feed back the Tx outputs to the appropriate Rx output. This way the data driven at the Tx input appears at the corresponding Rx output (refer to “Typical Operating Circuit” on page 6). The Tx outputs remain connected to their terminals, so the external loads are reflected in the loopback performance. This allows the loopback function to potentially detect some common bus faults such as one or both driver outputs shorted to GND, or outputs shorted together. ISL81334 CONNECTOR A1 B1 R RA1 Y1 Z1 D DY1 Z2 Y2 DY2 UART OR ASIC OR µCONTROLLER RA2 B2 A2 FIGURE 11. ILLUSTRATION OF FLOW THROUGH PINOUT Low Power Shutdown (SHDN) Mode The ON/OFF pin is driven low to place the IC (both ports) in the SHDN mode, and the already low supply current drops to as low as 25µA. If this functionality isn’t desired, the pin can be left disconnected (thanks to the internal pull-up), or it should be connected to VCC (VL for the QFN), through a 1kΩ resistor. SHDN disables the Tx and Rx outputs, and disables the charge pumps if either port is in RS-232 mode, so V+ collapses to VCC, and V- collapses to GND. 17 Note that the loopback mode uses an additional set of receivers, as shown in “Typical Operating Circuit” on page 6. These loopback receivers are not standards compliant, so the loopback mode can’t be used to implement a half-duplex RS-485 transceiver. If loopback won’t be utilized, the pin can be left disconnected (thanks to the internal pull-up), or it should be connected to VCC (VL for the QFN), through a 1kΩ resistor. ISL41334 (QFN Package) Special Features Logic Supply (VL Pin) The ISL41334 (QFN) includes a VL pin that powers the logic inputs (Tx inputs and control pins) and Rx outputs. These pins interface with “logic” devices such as UARTs, ASICs, and µcontrollers, and today most of these devices use power supplies significantly lower than 5V. Thus, a 5V output level from a 5V powered dual protocol IC might seriously overdrive and damage the logic device input. Similarly, the FN6202.3 November 21, 2007 ISL81334, ISL41334 the logic device’s low VOH might not exceed the VIH of a 5V powered dual protocol input. Connecting the VL pin to the power supply of the logic device (as shown in Figure 12) limits the ISL41334’s Rx output VOH to VL (see Figure 15), and reduces the Tx and control input switching points to values compatible with the logic device output levels. Tailoring the logic pin input switching points and output levels to the supply voltage of the UART, ASIC, or µcontroller eliminates the need for a level shifter/translator between the two ICs. VCC = +5V RA DY GND VCC = +2V VOH = 5V RXD VIH ≥ 2V VOH ≤ 2V ISL81334 ESD DIODE TXD GND UART/PROCESSOR VCC = +5V VCC = +2V VL RA VOH = 2V RXD The VL supply current (IL) is typically less than 100µA, as shown in Figures 20 and 21. All of the DC VL current is due to inputs with internal pull-up resistors (DE, SP, LB, ON/OFF) being driven to the low input state. The worst case IL current occurs during SHDN (see Figure 20), due to the IL through the ON/OFF pin pull-up resistor when that pin is driven low. IIL through an input pull-up resistor is ~20µA, so the IL in Figure 20 drops by about 40µA (at VL = 5V) when the two SP inputs are high (middle vs top curve). IL is lowest in the RS-232 mode, because only the ON/OFF pin should be driven low. When all these inputs are driven high, IL drops to <1µA, so to minimize power dissipation drive these inputs high when unneeded (e.g., SP inputs aren’t used in RS-232 mode, so drive them high). Active Low Rx Enable (RXEN) In many RS-485 applications, especially half duplex configurations, users like to accomplish “echo cancellation” by disabling the corresponding receiver while its driver is transmitting data. This function is available on the QFN package via an active low RXEN pin for each port. The active low function also simplifies direction control, by allowing a single Tx/Rx direction control line. If an active high RXEN were used, either two valuable I/O pins would be used for direction control, or an external inverter is required between DE and RXEN. Figure 13 details the advantage of using the RXEN pin. ESD DIODE +5V ISL81387 + VCC DY GND RA VIH = 0.9V VOH ≤ 2V TXD GND A DEN Y DY ISL41334 B R RXEN Tx/Rx D Z GND UART/PROCESSOR FIGURE 12. USING VL PIN TO ADJUST LOGIC LEVELS ACTIVE HIGH RX ENABLE VL can be anywhere from VCC down to 1.65V, but the input switching points may not provide enough noise margin when VL < 1.8V. Table 5 indicates typical VIH and VIL values for various VL values so the user can ascertain whether or not a particular VL voltage meets his needs. TABLE 5. VIH AND VIL vs VL FOR VCC = 5V VL (V) VIH (V) VIL (V) 1.65V 0.79 0.50 1.8V 0.82 0.60 2.0V 0.87 0.69 2.5V 0.99 0.86 3.3V 1.19 1.05 18 0.1µF +5V ISL41334 + VCC RA R 0.1µF B A RXEN * Tx/Rx DE DY Y D Z GND * QFN ONLY ACTIVE LOW RX ENABLE FIGURE 13. USING ACTIVE LOW vs ACTIVE HIGH RX ENABLE FN6202.3 November 21, 2007 ISL81334, ISL41334 RS-485 Slew Rate Limited Data Rates The SOIC and SSOP versions of this IC operate with Tx output transitions optimized for a 20Mbps data rate. These fast edges may increase EMI and reflection issues, even though fast transitions aren’t required at the lower data rates used by many applications. The ISL41334 (QFN version) solves this problem by offering two additional, slew rate limited, data rates that are optimized for speeds of 115kbps, and 460kbps.The slew limited edges permit longer unterminated networks, or longer stubs off terminated busses, and help minimize EMI and reflections. Nevertheless, for the best jitter performance when driving long cables, the faster speed options may be preferable, even at lower data rates. The faster output transitions deliver less variability (jitter) when loaded with the large capacitance associated with long cables. Figures 43, 44, and 45 detail the jitter performance of the three speed options while driving three different cable lengths. The figures show that under all conditions the faster the edge rate, the better the jitter performance. Of course, faster transitions require more attention to ensuring short stub lengths, and quality terminations, so there are trade-offs to be made. Assuming a Typical Performance Curves jitter budget of 10%, it is likely better to go with the slow speed option for data rates of 115kbps or less, to minimize fast edge effects. Likewise, the medium speed option is a good choice for data rates between 115kbps and 460kbps. For higher data rates, or when the absolute best jitter is required, use the high speed option. Speed selection is via the SPA and SPB pins (see Table 3), and the selection pertains to each port programmed for RS-485 mode. Evaluation Board An evaluation board, part number ISL41334EVAL1, is available to assist in assessing the dual protocol IC’s performance. The evaluation board contains a QFN packaged device, but because the same die is used in all packages, the board is also useful for evaluating the functionality of the other versions. The board’s design allows for evaluation of all standard features, plus the QFN specific features. Refer to the eval board application note for details, and contact your sales rep for ordering information. VCC = VL = 5V, TA = +25°C; Unless Otherwise Specified. 5 VOL, +25°C 40 HIGH OUTPUT VOLTAGE (V) RECEIVER OUTPUT CURRENT (mA) 50 VOL, +85°C 30 20 VOH, +25°C VOH, +85°C 10 4 3 IOH = -1mA 2 IOH = -8mA 1 IOH = -4mA 0 0 1 2 3 4 0 5 0 1 2 RECEIVER OUTPUT VOLTAGE (V) FIGURE 14. RECEIVER OUTPUT CURRENT vs RECEIVER OUTPUT VOLTAGE 5 FIGURE 15. RECEIVER HIGH OUTPUT VOLTAGE vs LOGIC SUPPLY VOLTAGE (VL) DIFFERENTIAL OUTPUT VOLTAGE (V) DRIVER OUTPUT CURRENT (mA) 4 3.6 100 90 80 70 60 50 40 30 20 10 0 3 VL (V) 0 1 2 3 4 DIFFERENTIAL OUTPUT VOLTAGE (V) FIGURE 16. RS-485, DRIVER OUTPUT CURRENT vs DIFFERENTIAL OUTPUT VOLTAGE 19 5 3.5 RDIFF = 100Ω 3.4 3.3 3.2 RDIFF = 54Ω 3.1 3.0 -40 -25 0 25 50 75 85 TEMPERATURE (°C) FIGURE 17. RS-485, DRIVER DIFFERENTIAL OUTPUT VOLTAGE vs TEMPERATURE FN6202.3 November 21, 2007 ISL81334, ISL41334 Typical Performance Curves VCC = VL = 5V, TA = +25°C; Unless Otherwise Specified. (Continued) 150 4.0 Y OR Z = LOW RS-232, RXEN = X FULL TEMP RANGE 3.5 50 3.0 ICC (mA) OUTPUT CURRENT (mA) 100 0 Y OR Z = HIGH -50 RS-485, HALF DUPLEX, DE = VCC, RXEN = X 2.0 +25°C +85°C 2.5 RS-485, FULL DUPLEX, DE = VCC, RXEN = X -100 1.5 -40°C RS-485, DE = GND, RXEN = X -150 -7 -6 -4 -2 0 2 4 6 OUTPUT VOLTAGE (V) 8 10 1.0 -40 12 0 -25 50 25 85 75 TEMPERATURE (°C) FIGURE 18. RS-485, DRIVER OUTPUT CURRENT vs SHORT CIRCUIT VOLTAGE FIGURE 19. SUPPLY CURRENT vs TEMPERATURE 10m 600 NO LOAD VIN = VL or GND LB = VL VL ≤ VCC VL > VCC NO LOAD VIN = VL or GND LB = VL ON = DZ/DE = DY = GND 500 RS-232/RS-485 ICC 1m ICC AND IL (μA) IL (A) 400 RS-485, DE = ON = SP = GND 100µ 200 RS-232, ON = GND, SP = VL 10µ 100 RS-485, DE = ON = GND, SP = VL 1µ 300 2 3 4 5 6 VL (V) FIGURE 20. RS-232, VL SUPPLY CURRENT vs VL VOLTAGE (QFN ONLY) 20 SP = GND RS-485 IL 0 2.0 2.5 SP = VL RS-232 IL 3.0 3.5 4.0 4.5 5.0 VL (V) FIGURE 21. VCC and VL SHDN SUPPLY CURRENTS vs VL VOLTAGE (QFN ONLY) FN6202.3 November 21, 2007 ISL81334, ISL41334 Typical Performance Curves VCC = VL = 5V, TA = +25°C; Unless Otherwise Specified. (Continued) 400 1700 RDIFF = 54Ω, CL = 100pF RDIFF = 54Ω, CL = 100pF 350 |tPHLZ - tPLHY| 300 1600 SKEW (ns) PROPAGATION DELAY (ns) 1650 tDHL 1550 tDLH |tPLHZ - tPHLY| 250 200 150 1500 100 tDHL 1450 |tDLH - tDHL| 50 1400 -40 0 -25 50 25 75 -40 85 0 -25 25 50 85 75 TEMPERATURE (°C) TEMPERATURE (°C) FIGURE 22. RS-485, DRIVER PROPAGATION DELAY vs TEMPERATURE (SLOW DATA RATE, QFN ONLY) FIGURE 23. RS-485, DRIVER SKEW vs TEMPERATURE (SLOW DATA RATE, QFN ONLY) 560 120 RDIFF = 54Ω, CL = 100pF RDIFF = 54Ω, CL = 100pF 550 530 |tPHLZ - tPLHY| 80 SKEW (ns) PROPAGATION DELAY (ns) 100 540 520 tDHL 510 tDLH 500 60 |tPLHZ - tPHLY| 40 tDHL 490 20 480 |tDLH - tDHL| 470 -40 -25 0 50 25 75 0 -40 85 0 -25 TEMPERATURE (°C) 85 75 FIGURE 25. RS-485, DRIVER SKEW vs TEMPERATURE (MEDIUM DATA RATE, QFN ONLY) 2.5 RDIFF = 54Ω, CL = 100pF RDIFF = 54Ω, CL = 100pF 2.0 35 |tDLH - tDHL| tDHL SKEW (ns) PROPAGATION DELAY (ns) 50 TEMPERATURE (°C) FIGURE 24. RS-485, DRIVER PROPAGATION DELAY vs TEMPERATURE (MEDIUM DATA RATE, QFN ONLY) 40 25 30 tDLH 1.5 1.0 |tPLHZ - tPHLY| 25 0.5 20 -40 -25 0 25 50 75 TEMPERATURE (°C) FIGURE 26. RS-485, DRIVER PROPAGATION DELAY vs TEMPERATURE (FAST DATA RATE) 21 85 |tPHLZ - tPLHY| 0 -40 -25 0 25 50 75 85 TEMPERATURE (°C) FIGURE 27. RS-485, DRIVER SKEW vs TEMPERATURE (FAST DATA RATE) FN6202.3 November 21, 2007 ISL81334, ISL41334 RA 0 5 4 3 2 Y Z 1 0 RA 0 5 4 Z 3 2 1 Y 0 TIME (400ns/DIV) RA 0 5 4 3 2 RECEIVER OUTPUT (V) 0 DRIVER INPUT (V) 5 5 FIGURE 29. RS-485, DRIVER AND RECEIVER WAVEFORMS, HIGH TO LOW (SLOW DATA RATE, QFN ONLY) DRIVER OUTPUT (V) DRIVER OUTPUT (V) RECEIVER OUTPUT (V) FIGURE 28. RS-485, DRIVER AND RECEIVER WAVEFORMS, LOW TO HIGH (SLOW DATA RATE, QFN ONLY) RDIFF = 60Ω, CL = 100pF Y Z 1 0 RDIFF = 60Ω, CL = 100pF DY 5 5 4 3 2 1 Z Y 0 0 4 DRIVER OUTPUT (V) 5 Y 3 2 FIGURE 31. RS-485, DRIVER AND RECEIVER WAVEFORMS, HIGH TO LOW (MEDIUM DATA RATE, QFN ONLY) RECEIVER OUTPUT (V) RA DRIVER INPUT (V) RECEIVER OUTPUT (V) DRIVER OUTPUT (V) 5 0 5 Z 1 0 TIME (10ns/DIV) FIGURE 32. RS-485, DRIVER AND RECEIVER WAVEFORMS, LOW TO HIGH (FAST DATA RATE) 22 0 TIME (200ns/DIV) FIGURE 30. RS-485, DRIVER AND RECEIVER WAVEFORMS, LOW TO HIGH (MEDIUM DATA RATE, QFN ONLY) DY 5 RA 0 TIME (200ns/DIV) RDIFF = 60Ω, CL = 100pF 0 5 TIME (400ns/DIV) DY 5 DRIVER INPUT (V) 5 DY DRIVER INPUT (V) 0 RDIFF = 60Ω, CL = 100pF RDIFF = 60Ω, CL = 100pF DY 5 0 RA 0 5 DRIVER INPUT (V) DY 5 RECEIVER OUTPUT (V) RDIFF = 60Ω, CL = 100pF DRIVER INPUT (V) VCC = VL = 5V, TA = +25°C; Unless Otherwise Specified. (Continued) DRIVER OUTPUT (V) DRIVER OUTPUT (V) RECEIVER OUTPUT (V) Typical Performance Curves 5 4 Z 3 2 1 Y 0 TIME (10ns/DIV) FIGURE 33. RS-485, DRIVER AND RECEIVER WAVEFORMS, HIGH TO LOW (FAST DATA RATE) FN6202.3 November 21, 2007 ISL81334, ISL41334 Typical Performance Curves VCC = VL = 5V, TA = +25°C; Unless Otherwise Specified. (Continued) VOUT+ 5.0 2.5 ALL TOUTS LOADED WITH 3kΩ TO GND 0 1 TRANSMITTER/PORT AT 250kbps or 500kbps, OTHER TRANSMITTERS AT 30kbps -2.5 500kbps -5.0 -7.5 500kbps VOUT 250kbps 0 1000 2000 3000 4000 TRANSMITTER OUTPUT VOLTAGE (V) 7.5 250kbps RS-232 REGION OF NONCOMPLIANCE TRANSMITTER OUTPUT VOLTAGE (V) 7.5 5.0 VOUT+ 2.5 OUTPUTS STATIC ALL TOUTS LOADED WITH 3kΩ TO GND 0 -2.5 -5.0 VOUT - -7.5 -40 5000 -25 0 25 50 75 85 TEMPERATURE (°C) LOAD CAPACITANCE (pF) FIGURE 34. RS-232, TRANSMITTER OUTPUT VOLTAGE vs LOAD CAPACITANCE FIGURE 35. RS-232, TRANSMITTER OUTPUT VOLTAGE vs TEMPERATURE TRANSMITTER OUTPUT CURRENT (mA) 40 CL = 3500pF, 1 CHANNEL SWITCHING/PORT 30 5 Y or Z = LOW DY 20 0 10 5 VOUT SHORTED TO GND 0 0 Y/A -10 -5 -20 5 Y or Z = HIGH -30 0 -40 -40 -25 0 50 25 TEMPERATURE (°C) 75 FIGURE 36. RS-232, TRANSMITTER SHORT CIRCUIT CURRENT vs TEMPERATURE RA 85 2µs/DIV FIGURE 37. RS-232, TRANSMITTER AND RECEIVER WAVEFORMS AT 250kbps 60 VIN = ±5V CL = 1000pF, 1 CHANNEL SWITCHING/PORT RECEIVER + DUTY CYCLE (%) 5 DY 0 5 0 Y/A -5 5 RA 0 FULL TEMP RANGE 58 56 54 SR IN = 15V/μs 52 SR IN = 100V/μs 50 48 50 1μs/DIV. FIGURE 38. RS-232, TRANSMITTER AND RECEIVER WAVEFORMS AT 500kbps 23 500 1000 1500 2000 DATA RATE (kbps) FIGURE 39. RS-232, RECEIVER OUTPUT + DUTY CYCLE vs DATA RATE FN6202.3 November 21, 2007 ISL81334, ISL41334 VCC = VL = 5V, TA = +25°C; Unless Otherwise Specified. (Continued) 1000 ALL TOUTS LOADED WITH 5kΩ TO GND 900 DATA RATE (kbps) 7.5 VOUT ≥ ±4V 800 700 2 TRANSMITTERS AT +25°C 600 1 TRANSMITTER AT +25°C 500 400 300 200 1 TRANSMITTER AT +85°C 2 TRANSMITTERS AT +85°C 100 VOUT+ 5.0 +25°C +85°C 2.5 1 TRANSMITTER SWITCHING ON EACH PORT 0 ALL TOUTS LOADED WITH 5kΩ TO GND, CL = 1000pF -2.5 +85°C -5.0 VOUT - +25°C RS-232 REGION OF NONCOMPLIANCE 1100 TRANSMITTER OUTPUT VOLTAGE (V) Typical Performance Curves -7.5 100 1000 2000 3000 LOAD CAPACITANCE (pF) 4000 5000 0 100 200 300 400 500 600 700 800 DATA RATE (kbps) FIGURE 40. RS-232, TRANSMITTER MAXIMUM DATA RATE vs LOAD CAPACITANCE FIGURE 41. RS-232, TRANSMITTER OUTPUT VOLTAGE vs DATA RATE 450 100 1 TRANSMITTER SWITCHING ON EACH PORT 400 ALL TOUTS LOADED WITH 3kΩ TO GND, CL = 1000pF FAST 10 JITTER (%) 350 SKEW (ns) MED SLOW +85°C 300 250 1 +25°C 200 150 50 DOUBLE TERM’ED WITH 121Ω 0.1 150 250 350 450 550 650 750 32 100 200 300 400 500 600 700 800 900 1000 DATA RATE (kbps) DATA RATE (kbps) FIGURE 42. RS-232, TRANSMITTER SKEW vs DATA RATE FIGURE 43. RS-485, TRANSMITTER JITTER vs DATA RATE WITH 2000’ CAT-5 CABLE 100 100 SLOW SLOW MED MED 10 FAST JITTER (%) JITTER (%) 10 FAST 1 1 DOUBLE TERM’ED WITH 121Ω 0.1 32 100 200 300 400 500 600 700 800 900 1000 DATA RATE (kbps) FIGURE 44. RS-485, TRANSMITTER JITTER vs DATA RATE WITH 1000’ CAT-5 CABLE 24 DOUBLE TERM’ED WITH 121Ω 0.1 32 100 200 300 400 500 600 700 800 900 1000 DATA RATE (kbps) FIGURE 45. RS-485, TRANSMITTER JITTER vs DATA RATE WITH 350’ CAT-5 CABLE FN6202.3 November 21, 2007 ISL81334, ISL41334 Die Characteristics SUBSTRATE AND QFN THERMAL PAD POTENTIAL (POWERED UP): GND TRANSISTOR COUNT: 4838 PROCESS: BiCMOS 25 FN6202.3 November 21, 2007 ISL81334, ISL41334 Package Outline Drawing L40.6x6 40 LEAD QUAD FLAT NO-LEAD PLASTIC PACKAGE Rev 3, 10/06 4X 4.5 6.00 36X 0.50 A B 6 PIN 1 INDEX AREA 6 PIN #1 INDEX AREA 40 31 30 1 6.00 4 . 10 ± 0 . 15 21 10 0.15 (4X) 11 20 0.10 M C A B TOP VIEW 40X 0 . 4 ± 0 . 1 4 0 . 23 +0 . 07 / -0 . 05 BOTTOM VIEW SEE DETAIL "X" 0.10 C 0 . 90 ± 0 . 1 ( C BASE PLANE ( 5 . 8 TYP ) SEATING PLANE 0.08 C SIDE VIEW 4 . 10 ) ( 36X 0 . 5 ) C 0 . 2 REF 5 ( 40X 0 . 23 ) 0 . 00 MIN. 0 . 05 MAX. ( 40X 0 . 6 ) DETAIL "X" TYPICAL RECOMMENDED LAND PATTERN NOTES: 1. Dimensions are in millimeters. Dimensions in ( ) for Reference Only. 2. Dimensioning and tolerancing conform to AMSE Y14.5m-1994. 3. Unless otherwise specified, tolerance : Decimal ± 0.05 4. Dimension b applies to the metallized terminal and is measured between 0.15mm and 0.30mm from the terminal tip. 5. Tiebar shown (if present) is a non-functional feature. 6. The configuration of the pin #1 identifier is optional, but must be located within the zone indicated. The pin #1 indentifier may be either a mold or mark feature. 26 FN6202.3 November 21, 2007 ISL81334, ISL41334 Small Outline Plastic Packages (SOIC) M28.3 (JEDEC MS-013-AE ISSUE C) N 28 LEAD WIDE BODY SMALL OUTLINE PLASTIC PACKAGE INDEX AREA H 0.25(0.010) M B M INCHES E SYMBOL -B- 1 2 3 L SEATING PLANE -A- h x 45o A D -C- e A1 B 0.25(0.010) M C 0.10(0.004) C A M B S 1. Symbols are defined in the “MO Series Symbol List” in Section 2.2 of Publication Number 95. MILLIMETERS MIN MAX NOTES A 0.0926 0.1043 2.35 2.65 - 0.0040 0.0118 0.10 0.30 - B 0.013 0.0200 0.33 0.51 9 C 0.0091 0.0125 0.23 0.32 - D 0.6969 0.7125 17.70 18.10 3 E 0.2914 0.2992 7.40 7.60 4 0.05 BSC 0.394 h 0.01 0.029 L 0.016 0.050 8o 0o N 0.419 1.27 BSC H α NOTES: MAX A1 e α MIN 10.00 - 0.25 0.75 5 0.40 1.27 6 28 0o - 10.65 28 7 8o Rev. 0 12/93 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 “E” does not include interlead flash or protrusions. Interlead flash and protrusions shall not exceed 0.25mm (0.010 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. The lead width “B”, as measured 0.36mm (0.014 inch) or greater above the seating plane, shall not exceed a maximum value of 0.61mm (0.024 inch) 10. Controlling dimension: MILLIMETER. Converted inch dimensions are not necessarily exact. 27 FN6202.3 November 21, 2007 ISL81334, ISL41334 Shrink Small Outline Plastic Packages (SSOP) M28.209 (JEDEC MO-150-AH ISSUE B) N 28 LEAD SHRINK SMALL OUTLINE PLASTIC PACKAGE INDEX AREA H 0.25(0.010) M B M INCHES E GAUGE PLANE -B1 2 3 L 0.25 0.010 SEATING PLANE -A- A D -C- α e B C 0.10(0.004) 0.25(0.010) M C A M SYMBOL MIN MAX MIN MAX NOTES A - 0.078 - 2.00 - A1 0.002 - 0.05 - - A2 0.065 0.072 1.65 1.85 - B 0.009 0.014 0.22 0.38 9 C 0.004 0.009 0.09 0.25 - D 0.390 0.413 9.90 10.50 3 E 0.197 0.220 5.00 5.60 4 e A2 A1 B S 0.026 BSC H 0.292 L 0.022 N α NOTES: MILLIMETERS 0.65 BSC 0.322 7.40 0.037 0.55 28 0° - 8.20 - 0.95 6 28 8° 0° 7 8° 1. Symbols are defined in the “MO Series Symbol List” in Section 2.2 of Publication Number 95. Rev. 2 6/05 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. 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 28 FN6202.3 November 21, 2007