ST3485E 3.3V POWERED, 15KV ESD PROTECTED, TRASMIT AT UP TO 12MBPS TRUE RS-485/RS-422 TRANSCEIVER ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ESD PROTECTION: ±15KV HUMAN BODY MODEL ±8KV IEC 1000-4-2 CONTACT DISCHARGE OPERATE FROM A SINGLE 3.3V SUPPLY NO CHARGE PUMP REQUIRED INTEROPERABLE WITH 5V LOGIC 1µA LOW CURRENT SHUTDOWN MODE MAX GUARANTEED 12 Mbps DATA RATE -7 TO 12 COMMON MODE INPUT VOLTAGE RANGE HALF DUPLEX VERSIONS AVAILABLE INDUSTRY STANDARD 75176 PINOUT CURRENT LIMITING AND THERMAL SHUTDOWN FOR DRIVER OVERLOAD PROTECTION GUARANTEED HIGH RECEIVER OUTPUT STATE FOR FLOATING INPUTS WITH NO SIGNAL PRESENT ALLOW UP TO 64 TRANSCEIVERS ON THE BUS DESCRIPTION The ST3485E is ±15kV ESD protected, 3.3V low power transceiver for RS-485 and RS-422 communications. The device contains one driver DIP SOP and one receiver in half duplex configuration. The ST3485E transmit and receive at guaranteed data rate at least to 12Mbps. All transmitter outputs and receiver inputs are protected to ±15kV using Human Body Model. Driver is short-circuit current limited and is protected against excessive power dissipation by thermal shutdown circuitry that place the driver outputs into a high-impedance state. The ST3485E input has a true fail-safe feature that guarantees a logic high output if both inputs are open circuit, shorted together or in presence of the termination with no signal on the bus. ORDERING CODES Type Temperature Range Package Comments ST3485ECN ST3485EBN ST3485ECD ST3485EBD ST3485ECDR ST3485EBDR 0 to 70 °C -40 to 85 °C 0 to 70 °C -40 to 85 °C 0 to 70 °C -40 to 85 °C DIP-8 DIP-8 SO-8 (Tube) SO-8 (Tube) SO-8 (Tape & Reel) SO-8 (Tape & Reel) 50parts per tube / 40tube per box 50parts per tube / 40tube per box 100parts per tube / 20tube per box 100parts per tube / 20tube per box 2500 parts per reel 2500 parts per reel October 2002 1/16 ST3485E PIN CONFIGURATION PIN DESCRIPTION PlN N° SYMBOL 1 RO 2 RE 3 DE 4 DI 5 6 7 GND A B VCC 8 NAME AND FUNCTION Receiver Output. If A>B by 200mV, RO will be high; if A<B by 200mV, RO will be low Receiver Output Enable. RO is enabled when RE is low; RO is high impedance when RE is high. If RE is high and DE is low, the device will enter a low power shutdown mode. Driver Output Enable. The driver outputs are enabled by bringing DE high. They are high impedance when DE is low. If RE is high DE is low, the device will enter a low-power shutdown mode. If the driver outputs are enabled, the part functions as line driver, while they are high impedance, it functions as line receivers if RE is low. Driver Input. A low on DI forces output A low and output B high. Similarly, a high on DI forces output A high and output B low Ground Non-inverting Receiver Input and Non-inverting Driver Output Inverting Receiver Input and Inverting Driver Output Supply Voltage: VCC= 3V to 3.6V TRUTH TABLE (RECEIVER) TRUTH TABLE (DRIVER) INPUTS OUTPUTS INPUTS OUTPUT MODE RE DE DI B A X X L H H H L L H L X X L H Z Z H L Z Z X= Don’t Care; Z=High Impedance MODE RE DE Normal Normal Normal Shutdown L L L L H L L L L L A-B RO ≥ -0.015V ≤ -0.2V Inputs Open Inputs Shorted X H L H H Z X= Don’t Care; Z=High Impedance 2/16 Normal Normal Normal Normal Shutdown ST3485E ABSOLUTE MAXIMUM RATINGS Symbol VCC VI Parameter Value Supply Voltage Unit 7 V -0.3 to 7 V -0.3 to 7 V -7.5 to 12.5 V Control Input Voltage (RE, DE) VDI Driver Input Voltage (DI) VDO Driver Output Voltage (A, B) VRI Receiver Input Voltage (A, B) -7.5 to 12.5 V VRO Receiver Output Voltage (RO) -0.3 to (VCC + 0.3) V Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is not implied. ESD PERFORMANCE: TRANSMITTER OUTPUTS, RECEIVER INPUTS Symbol ESD ESD Parameter ESD Protection Voltage ESD Protection Voltage Test Conditions Min. Typ. Max. ± 15 ±8 Human Body Model IEC-1000-4-2 Contact Disharge Unit KV KV ELECTRICAL CHARACTERISTICS VCC = 3V to 3.6V, TA = -40 to 85°C, unless otherwise specified. Typical values are referred to TA = 25°C) Symbol Parameter ISUPPLY VCC Power Supply Current ISHDN Shutdown Supply Current Test Conditions No Load, DI=0V or VCC Min. Typ. Max. Unit DE=VCC, RE=0V or VCC 1.3 2.2 mA DE=0V, RE=0V 1.2 1.9 mA 0.002 1 µA DE=0V, RE=VCC, DI=0V or VCC LOGIC INPUT ELECTRICAL CHARACTERISTICS VCC = 3V to 3.6V, TA = -40 to 85°C, unless otherwise specified. Typical values are referred to TA = 25°C) Symbol Parameter VIL Input Logic Threshold Low Test Conditions Min. DE, DI, RE VIH Input Logic Threshold High DE, DI, RE IIN1 Logic Input Current DE, DI, RE IIN2 Input Current (A, B) DE=0V, VCC= 0 or 3.6V Typ. Max. Unit 1.3 0.8 V ± 2.0 µA 2 V VIN=12V 1 mA VIN=-7V -0.8 mA 3/16 ST3485E TRANSMITTER ELECTRICAL CHARACTERISTICS VCC = 3V to 3.6V, TA = -40 to 85°C, unless otherwise specified. Typical values are referred to Ta = 25°C) Symbol VOD ∆VOD VOC ∆VOC IOSD Parameter Differential Drive Output Test Conditions Min. Typ. Max. Unit RL= 100Ω (RS-422) (Figure 1) 2 V RL= 54Ω (RS-485) (Figure 1) 1.5 V RL= 60Ω (RS-485) (Figure 2) 1.5 V Change in magnitude of RL= 54Ω or 100Ω (Figure 1) Driver Differential Output Voltage for Complementary Output States (Note1) Driver Common Mode RL= 54Ω or 100Ω (Figure 1) Output Voltage Change in magnitude of RL= 54Ω or 100Ω (Figure 1) Driver Common Mode Output Voltage (Note1) Driver Short Circuit Output Current 0.2 V 3 V 0.2 V ± 250 mA RECEIVER ELECTRICAL CHARACTERISTICS VCC = 3V to 3.6V, TA = -40 to 85°C, unless otherwise specified. Typical values are referred to Ta = 25°C) Symbol VTH ∆VTH VOH VOL IOZR RRIN IOSR 4/16 Parameter Test Conditions Min. Receiver Differential Threshold Voltage Receiver Input Hysteresis VCM = -7V to 12V, DE = 0 Receiver Output High Voltage Receiver Output Low Voltage 3-State (High Impedance) Output Current at Receiver Receiver Input Resistance IOUT = -4mA, VID = 200mV, (Figures 8,9) VCM = -7V to 12V 24 Receiver Short-Circuit Current VRO = 0V to VCC 7 Typ. -0.2 VCM = 0V Max. Unit -0.015 V 30 V 2 V IOUT = 4mA, VID = -200mV, (Figure 3) 0.4 V VCC = 3.6V ±1 µA 60 mA VO = 0V to VCC KΩ ST3485E DRIVER SWITCHING CHARACTERISTICS VCC = 3V to 3.6V, TA = -40 to 85°C, unless otherwise specified. Typical values are referred to Ta = 25°C) Symbol Parameter Test Conditions Min. Typ. 12 15 Max. Unit DR Maximum Data Rate tDD Differential Output Delay RL= 60Ω CL = 15pF, (Figures 4,5) 18 30 ns tTD Differential Output Transition Time Propagation Delay RL= 60Ω CL = 15pF, (Figures 4,5) 12 20 ns RL= 27Ω CL = 15pF, (Figures 8,9) 18 30 ns RL= 27Ω CL = 15pF, (Figures 8,9) 2 5 ns tPZL |tPLH - tPHL| Propagation Delay Skew (Note2) Output Enable Time RL= 110Ω (Figures 10,11) 19 35 ns tPZH Output Enable Time RL= 110Ω (Figures 6,7) 30 50 ns tPHZ Output Disable Time RL= 110Ω (Figures 6,7) 19 35 ns tPLZ Output Disable Time RL= 110Ω (Figures 10,11) 30 50 ns 1 3 ns 30 50 ns 19 35 ns tPLH tPHL tPDS Differential Output Delay Skew tZH(SHDN) Driver Enable from Shutdown to Output High tZL(SHDN) Driver Enable from Shutdown to Output Low tSKEW Mbps RECEIVER SWITCHING CHARACTERISTICS VCC = 3V to 3.6V, TA = -40 to 85°C, unless otherwise specified. Typical values are referred to Ta = 25°C) Symbol Typ. Max. Unit Propagation Delay VID =0V to 3V CL1 = 15pF, (Figures 12,13) 30 50 ns VID =0V to 3V CL1 = 15pF, (Figures 12,13) 1 3 ns tPZL |tPLH - tPHL| Propagation Delay Skew Output Enable Time CRL = 15pF (Figures 14-18) 10 20 ns tPZH Output Enable Time CRL = 15pF (Figures 14-18) 10 20 ns tPHZ Output Disable Time CRL = 15pF (Figures 14-18) 10 20 ns tPLZ Output Disable Time CRL = 15pF (Figures 14-18) 10 20 ns CRL = 15pF (Figures 14-18) 10 20 ns CRL = 15pF (Figures 14-18) 20 40 ns tPLH tPHL tRPDS Parameter tZH(SHDN) Receiver Enable from Shutdown to Output High tZL(SHDN) Receiver Enable from Shutdown to Output Low Test Conditions Min. Note 1: ∆VOD and ∆VOC are the changes in VOD and VOC , respectively, when the DI input changes state. Note 2: measured on |tPLH(A)-tPHL (A)| and |tPLH(B)-tPHL(B)| Note 3: The transceivers are put into shutdown by bring RE high and DE low. If the input are in state for less than 80ns, the part are guarenteed not to enter shutdown. If the inputs are in this state for at least 300ns, the parts are guarenteed to have entered shutdown. 5/16 ST3485E TEST CIRCUITS AND TYPICAL CHARACTERISTICS Figure 1 : Driver and VOC Test Load Figure 2 : Driver VOD with Varying Common Mode Voltage Test Load Figure 3 : Receiver VOH and VOL Test Circuit 6/16 ST3485E Figure 4 : Drive Differential Output Delay Transition Time Test Circuit Figure 5 : Drive Differential Output Delay Transition Time Waveform Figure 6 : Drive Enable and Disable Times Test Circuit 7/16 ST3485E Figure 7 : Drive Enable and Disable Times Waveforms Figure 8 : Drive Propagation Time Test Circuit Figure 9 : Drive Propagation Time Waveform 8/16 ST3485E Figure 10 : Drive Enable and Disable Times Test Circuit Figure 11 : Drive Enable and Disable Times Waveforms Figure 12 : Receiver Propagation Delay Time Test Circuit 9/16 ST3485E Figure 13 : Receiver Propagation Delay Time Waveforms Figure 14 : Receiver Enable and Disable Times Test Circuit Figure 15 : Receiver Enable and Disable Times Waveform 10/16 ST3485E Figure 16 : Receiver Enable and Disable Times Waveform Figure 17 : Receiver Enable and Disable Times Waveform Figure 18 : Receiver Enable and Disable Times Waveform 11/16 ST3485E Figure 19 : Receiver Output Current vs Output Low Voltage Figure 22 : High Level Driver Output Capability Figure 20 : Receiver Output Current vs Output High Voltage Figure 23 : Receiver Input Characteristics Figure 21 : Low Level Driver Output Capability Figure 24 : Driver Short Circuit Current 12/16 ST3485E Figure 25 : Driver Short Circuit Current 13/16 ST3485E Plastic DIP-8 MECHANICAL DATA mm. inch DIM. MIN. A TYP MAX. MIN. 3.3 TYP. MAX. 0.130 a1 0.7 B 1.39 1.65 0.055 0.065 B1 0.91 1.04 0.036 0.041 b b1 0.028 0.5 0.38 0.020 0.5 D 0.015 0.020 9.8 0.386 E 8.8 0.346 e 2.54 0.100 e3 7.62 0.300 e4 7.62 0.300 F 7.1 0.280 I 4.8 0.189 L Z 3.3 0.44 0.130 1.6 0.017 0.063 P001F 14/16 ST3485E SO-8 MECHANICAL DATA DIM. mm. MIN. TYP A a1 inch MAX. MIN. TYP. 1.75 0.1 0.068 0.25 a2 MAX. 0.003 0.009 1.65 0.064 a3 0.65 0.85 0.025 0.033 b 0.35 0.48 0.013 0.018 b1 0.19 0.25 0.007 0.010 C 0.25 0.5 0.010 0.019 c1 45˚ (typ.) D 4.8 5.0 0.189 0.196 E 5.8 6.2 0.228 0.244 e 1.27 0.050 e3 3.81 0.150 F 3.8 4.0 0.149 0.157 L 0.4 1.27 0.015 0.050 M S 0.6 0.023 8˚ (max.) 0016023 15/16 ST3485E Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement 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 STMicroelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. © The ST logo is a registered trademark of STMicroelectronics © 2002 STMicroelectronics - Printed in Italy - All Rights Reserved STMicroelectronics GROUP OF COMPANIES Australia - Brazil - Canada - China - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan - Malaysia - Malta - Morocco Singapore - Spain - Sweden - Switzerland - United Kingdom - United States. © http://www.st.com 16/16