Standard Products ACT4485 Dual RS485 Interface Transceiver Radiation Tolerant www.aeroflex.com/RadHard October 8, 2008 FEATURES Radiation Performance - Total dose > 100 krad (Si) Designed for RS485 Interface Applications Single +5V supply +5V to -7V Bus common mode range source output Driver maintains high impedance in three-state or with the power off Combined Impedance of a driver output and receiver allows up to 32 transceivers on the bus 200 mV typical input hysteresis Voltage source output Receiver output Hi for Vin Diff = 0V < 5ns skew between BUS and BUSN complementary outputs 0.63"sq. x 0.125"ht, 18 lead, hermetic flat package Monolithic construction Designed for commercial, industrial and aerospace applications Plainview is a Class H & K MIL-PRF-38534 manufacturer Note: Aeroflex Plainview does not currently have a DSCC certified Radiation Hardened Assurance Program. VCC DI DR BUS BUSN DE Channel 1 or 2 Rx OUT Rx Rx EN GND FIGURE 1 - SCHEMATIC GENERAL DESCRIPTION The Aeroflex-Plainview ACT4485 is a monolithic dual bus/line transceiver designed for multipoint data transmission standard RS485 applicatons. The ACT4485 meets TIA/EIA -485 requirements. The receiver has a fail-safe feature which guarantees a high output state when the BUS is open or shorted. SCD4485 Rev B ABSOLUTE MAXIMUM RATINGS Operating Case Temperature -55C to +125C Storage Case Temperature -65C to +150C Power Supply Voltages (VCC) +12VDC Control Input Voltage -0.5 VDC to Vcc + 0.5VDC Driver Input Voltage -0.5 VDC to Vcc + 0.5VDC Driver Output Voltage 5V Receiver Input Voltage 5V Receiver Output Voltages -0.5 VDC to Vcc + 0.5VDC ELECTRICAL CHARACTERISTICS 1/ 2/ Parameter Condition Symbol Min Typ Max Unit IO = 0 VOD1 2.5 - 5 Vp-p VOD2 2.5 - 5 Vp-p VOD - - 0.2 Vp-p VOC - 2.55 3 V |VOC| - - 0.2 V VIH 2.4 - - V VIL - 0.8 V IIN 1 2 A -0.1 V Differential driver output voltage (unloaded) Differential driver output voltage (with load) See Figure 2 Change in magnitude of driver differential output Voltage for complementary states Driver common mode output voltage Change in magnitude of driver common-mode output Voltage for complementary states Input high voltage DE, DI, RE Input low voltage Input current -6.5V VCM +5V VTH -0.5 Receiver input hysteresis VCM = 0 VTH - 160 400 mV Receiver output high voltage IO = 4mA VOH 4.0 - - V Receiver output low voltage IO = -4mA VOL - - 0.5 V Differential input threshold voltage for receiver Receiver threshold - RX THLD -500 -400 -100 mVp Receiver input differential resistance - RIN DIFF 30K - - Receiver input common-mode resistance - RIN CM 8K - - Driver short-circuit current - IOS 70 100 140 mA VOH to GND or VOL to Vcc IOSR 7 22 85 mA Receiver short-circuit current STATIC DC POWER SUPPLY CURRENTS Parameter Conditions Supply current Sym Min Typ Max Unit See Below Table Channel 2 (1) Outputs All disabled Channel 1 (2) Outputs Note DE DI RE DRVout Load 0V 5V 5V X X X 0V 0V 0V HiZ LoZ LoZ X NL 60 Icc1 Icc2 Icc3 ICC1 - 8.2 - mA ICC2 - 21.3 - mA ICC3 - 43 - mA X = Hi/Lo, 0V = GND, 5V = 5VDC, HiZ = high impedance, LoZ = low impedance, NL = No Load Aeroflex Plainview SCD4485 Rev B 10/8/08 2 SWITCHING CHARACTERISTICS 1/ 2/ Parameter Condition Symbol Min Typ Max Unit RDIFF = 60 See test ckt Figure 2 tPLH - 125 200 nS tPHL - 80 150 nS tSKEW - 1 5 nS Driver rise or fall time tr, tf - 80 150 nS Driver Output enable delay tZH - 200 250 nS Driver Output disable delay tLZ - 230 300 nS tPLH - 40 100 nS tPHL - 60 100 nS Receiver rise or fall time tr, tf - 36 50 nS Receiver enable delay tZL - 100 150 nS Receiver disable delay tZH - 50 150 nS Driver input to output delay Driver input to output delay Driver output to output delay IO = 0 See test ckt Figure 2 Receiver input to output delay Notes: 1. Min/Max values are for VCC = +5V 5%, TC = -55C to +125C. Typical values are measured at VCC = +5V and TC = +25C. 2. Current measurements are for both channels. DRIVER FUNCTION TABLE Inputs DI RECEIVER FUNCTION TABLE Outputs DIFF Input BUS N RE Output > -100mV L H DE BUS H H/OPEN H L < -500mV L L L H/OPEN L H -500mV < VID < -100mV L H X L OFF HiZ OFF HiZ X H/OPEN H OPEN X H SHORT X H CSHLD 1500pF R 30 BUS VODIFF DI + CDIFF 200pF BUSN RX OUT IOUT - R Voc 30 CL 40pF CSHLD 1500pF DE RE FIGURE 2 - DRIVER/RECEIVER TIMING TEST CIRCUIT (Channel 1 or 2) Aeroflex Plainview SCD4485 Rev B 10/8/08 3 DI 3V 1.5V DI 1.5V 0V t PLH t PHL 1/2 VO VBUS VBUSN VOC VBUS VBUSN 1/2 VO tSKEW t SKEW VODIFF = VBUS - VBUSN VO 0V, VODIFF -VO 90% 80% 20% 10% tf tr FIGURE 3 - DRIVER SWITCHING WAVEFORMS FIGURE 3A - TYPICAL DRIVER OUTPUTS Aeroflex Plainview SCD4485 Rev B 10/8/08 4 VOH Rx Out VOL 1.5V 1.5V t PLH t PHL VODIFF VOD2 0V, VODIFF 0V -VOD2 FIGURE 4 - RECEIVER SWITCHING WAVEFORMS FIGURE 4A - TYPICAL RECEIVER OUTPUTS Aeroflex Plainview SCD4485 Rev B 10/8/08 5 ACT4485 88379 MADE IN THE USA 4X R.020 PACKAGE CONFIGURATION OUTLINE Pin # Function Pin # Function 1 DRIVER ENABLE 1 10 VCC 2 RECEIVER ENABLE 1 11 GROUND 3 RECEIVER OUT 1 12 BUS 2 4 NC 13 BUSN 2 5 DRIVER IN 1 14 DRIVER IN 2 6 BUSN 1 15 NC 7 BUS 1 16 RECEIVER OUT 2 8 GROUND 17 RECEIVER ENABLE 2 9 VCC 18 DRIVER ENABLE 2 PIN # vs FUNCTION TABLE Aeroflex Plainview SCD4485 Rev B 10/8/08 6 CONFIGURATIONS AND ORDERING INFORMATION Model No. Specifications Military Temperature, -55C to +125C Screened in accordance with MIL-PRF-38534, Class K ACT4485-S ACT4485-7 Case Flat Pack Commercial Flow, +25C testing only EXPORT CONTROL: EXPORT WARNING: This product is controlled for export under the International Traffic in Arms Regulations (ITAR). A license from the U.S. Department of State is required prior to the export of this product from the United States. Aeroflex's military and space products are controlled for export under the International Traffic in Arms Regulations (ITAR) and may not be sold or proposed or offered for sale to certain countries. (See ITAR 126.1 for complete information.) PLAINVIEW, NEW YORK Toll Free: 800-THE-1553 Fax: 516-694-6715 INTERNATIONAL Tel: 805-778-9229 Fax: 805-778-1980 NORTHEAST Tel: 603-888-3975 Fax: 603-888-4585 SE AND MID-ATLANTIC Tel: 321-951-4164 Fax: 321-951-4254 WEST COAST Tel: 949-362-2260 Fax: 949-362-2266 CENTRAL Tel: 719-594-8017 Fax: 719-594-8468 www.aeroflex.com info-ams@aeroflex.com Aeroflex Microelectronic Solutions reserves the right to change at any time without notice the specifications, design, function, or form of its products described herein. All parameters must be validated for each customer's application by engineering. No liability is assumed as a result of use of this product. No patent licenses are implied. Our passion for performance is defined by three attributes represented by these three icons: solution-minded, performance-driven and customer-focused SCD4485 Rev B 10/8/08 7