TP8485E

TP8485E 3PEAK | Alldatasheet

Document overview

• Manufacturer or author: Provided By alldatasheet.com(free datasheet download site)
• PDF pages: 17

Technical content

Features

◼ Exceeds Requirements of EIA-485 Standard ◼ Hot Plug Circuitry - Tx and Rx Outputs Remain Three-State During Power-up/Power-down ◼ Data Rate: Up to 250 kbps ◼ Full Fail-safe (Open, Short, Terminated) Receivers ◼ Up to 256 Nodes on a Bus (1/8 unit load) ◼ Wide Supply Voltage 3V to 5.5V ◼ SOIC-8 Package for Backward Compatibility ◼ Bus-Pin Protection: – ±12 kV HBM protection

Applications

⚫ E-Metering Networks ⚫ Industrial Automation ⚫ HVAC Systems ⚫ Process Control ⚫ DMX512-Networks ⚫ Battery-Powered Applications Pin Configuration (Top View)

Description

The TP8485E are 3V~5.5V powered transceivers that meet the RS -485 and RS -422 standards for balanced communication. Driver outputs and receiver i nputs are protected against ±12kV ESD strikes without latch-up. Transmitters in this family deliver exceptional differential output voltages (2.5V min/5Vcc), into the RS-485 required 54Ω load, for better noise immunity, or to allow up to eight 120Ω terminations in “star” topologies. These devices have very low bus currents so they present a true “1/8 unit load” to the RS -485 bus. This allows up to 256 transceivers on the network without using repeaters. Receiver (Rx) inputs feature a “Full Fail -Safe” design, which ensures a logic high Rx output if Rx inputs are floating, shorted, or on a terminated but undriven bus. Rx outputs feature high drive levels - typically 25mA @ VOL = 1V (to ease the design of optocoupled isolated interfaces). The TP8485E is available in an SOIC-8 and MSOP -8 package, and is characterized from –40° C to 125° C. 3PEAK and the 3PEAK logo are registered trademarks of 3PEAK INCORPORATED. All other trademarks are the property of their respective owners. Exceptional Tx Drives Up To 256 Loads While Still Delivering 2.5V VOD 100 0.5 1 1.5 2 2.5 3 3.5 Driver Output Current (mA) Differential Output Voltage (V) +25 ℃ +85 ℃ RD=15Ω RD=20Ω RD=54Ω RD=100Ω

2 Rev. E.1 www.3peak.com TP8485E ± 12K ESD Protection, Full Fail-Safe RS-485 Transceiver

Revision History

2015/10/9 Rev. 0 Production release Version 0 2015/12/7 Rev. C Updated package information 2018/10/22 Rev. D Updated HBM ESD level 2020/7/20 Rev. E Updated typo of pinout name 2023/5/10 Rev. E.1 Updated typo of Recommended Operating Conditions Order Information Model Name Order Number Package Transport Media, Quantity Marking Information TP8485E TP8485E-SR 8-Pin SOIC Tape and Reel, 4,000 TP8485E TP8485E TP8485E-VR 8-Pin MSOP Tape and Reel, 3,000 TP8485E

± 12K ESD Protection, Full Fail-Safe RS-485 Transceiver www.3peak.com Rev. E.1 PINOUT DEFINITION PIN NO. PIN NAME I/O DESCRIPTION 1 RO Digital output Receiver Output. 2 /RE Digital input Receiver Output Enable. 3 DE Digital input Driver Output Enable. 4 DI Digital input Driver Input. 5 GND Ground Ground. 6 A/Y Bus input/output Noninverting Receiver Input A and Noninverting Driver Output A. 7 B/Z Bus input/output Inverting Receiver Input B and Inverted Driver Output B. 8 VCC Power Power Supply. DRIVER PIN FUNCTIONS INPUT ENABLE OUTPUTS H H H L Actively drives bus High L H L H Actively drives bus Low X L Z Z Driver disabled X OPEN Z Z Driver disabled by default OPEN H H L Actively drives bus High RECEIVER PIN FUNCTIONS DIFFERENTIAL INPUT ENABLE OUTPUT DESCRIPTION VID = VA – VB /RE RO NORMAL MODE VIT+ < VID L H Receive valid bus High VIT– < VID < VIT+ L ? Indeterminate bus state VID < VIT– L L Receive valid bus Low X H Z Receiver disabled X OPEN Z Receiver disabled Open, short, idle Bus L H Indeterminate bus state

4 Rev. E.1 www.3peak.com TP8485E ± 12K ESD Protection, Full Fail-Safe RS-485 Transceiver Absolute Maximum Ratings Input Voltages Input/Output Voltages Short Circuit Duration Recommended Operating Conditions Note 2 Thermal Resistance, ΘJA (Typical) Note 1: Tested according to TIA/EIA-485-A, Section 4.2.6 (±25V for 15μs at a 1% duty cycle). Note 2: 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.

± 12K ESD Protection, Full Fail-Safe RS-485 Transceiver www.3peak.com Rev. E.1

Electrical Characteristics

Test Conditions: VCC = 5V, Over operating free-air temperature range(unless otherwise noted) PARAMETER CONDITIONS MIN TYP MAX UNITS |VOD| Driver differential-output voltage magnitude RL = 60 Ω See Figure 1B 2.6 V RL = 54 Ω with VA or VB from –7 to +12 V, VCC = 5V (RS-485) See Figure 1A 2.1 2.5 RL = 54 Ω with VA or VB from –7 to +12 V, VCC = 3V (RS-485) 1 1.5 RL = 100 Ω(RS-422) 3 ⊿|VOD| Change in magnitude of driver differential-output voltage RL = 54 Ω, CL=50 pF, VCC = 5V See Figure 1A -0.2 -0.002 0.2 V VOC(SS) Steady-stage common-mode output voltage Center of two 27 Ω load resistors See Figure 1A VCC/2 V ⊿VOC Change in differential driver common-mode output voltage 0.05 V VOC(PP) Peak-to-peak driver common- mode output voltage 0.5 COD Differential output capacitance 8 pF VIT+ Positive-going receiver differential- input voltage threshold -40 mV VIT- Negative-going receiver differential-input voltage threshold -200 mV VHYS(1) Receiver differential-input voltage threshold hysteresis (VIT+ – VIT– ) 110 mV VIH Logic Input High Voltage DI, DE, RE 2 V VIL Logic Input Low Voltage DI, DE, RE 0.4 V VOH Receiver high-level output voltage IOH= -8 mA 4 4.5 V VOL Receiver low-level output voltage IOL= 8 mA 0.2 0.4 V II Driver input, driver enable and receiver enable input current -2 0.01 2 μA IOZ Receiver high-impedance output current VO = 0 V or VCC, /RE at VCC -2 0.01 2 μA |IOS| Driver short-circuit output current │IOS│ with VA or VB from –7 to +12 V 75 80 115 mA II Bus input current(driver disabled) VCC = 4.5 to 5.5 V or VCC = 0 V, DE at 0 V VI= 12 V 100 150 μA VI= -7 V -150 -80 ICC Supply current(quiescent) Driver and receiver enabled DE = VCC, /RE = GND, No LOAD 695 900 μA Driver enabled, receiver disabled DE = VCC, /RE = V CC, No LOAD 270 350 Driver disabled, receiver enabled DE = GND, /RE = VCC, No LOAD 480 600 Driver and receiver disabled DE = GND, /RE = VCC, DI= Vcc No LOAD 1.4 5

6 Rev. E.1 www.3peak.com TP8485E ± 12K ESD Protection, Full Fail-Safe RS-485 Transceiver Switching Characteristics PARAMETER CONDITIONS MIN TYP MAX UNITS DRIVER tr, tf Driver differential-output rise and fall times RL = 54 Ω, CL=50pF See Figure 2 620 ns tPHL, tPLH Driver propagation delay 340 tSK(P) Driver pulse skew, |tPHL – tPLH| 23 tPHZ, tPLZ Driver disable time See Figure 3 250 ns tPHZ, tPLZ Driver enable time Receiver enabled 562 ns Receiver disabled 562 RECEIVER tr, tf Receiver output rise and fall times CL=15 pF See Figure 5 12.4 ns tPHL, tPLH Receiver propagation delay time 960 tSK(P) Receiver pulse skew, |tPHL – tPLH| 40 tPHZ, tPLZ Receiver disable time 7 ns tPZL, tPZH Receiver enable time Driver enabled See Figure 6 70 ns Driver disabled See Figure 6 989 ESD RS-485 Pins (A, Y, B, Z, A/Y, B/Z) Human Body Model, From Bus Pins to GND ±12 kV All Other Pins Human Body Model, per MIL-STD-883 ±2 kV

± 12K ESD Protection, Full Fail-Safe RS-485 Transceiver www.3peak.com Rev. E.1 Detailed Description RS-485 and RS-422 are differential (balanced) data transmission standards used for long haul or noisy environments. RS-422 is a subset of RS -485, so RS-485 transceivers are also RS -422 compliant. RS-422 is a point -to-multipoint (multidrop) standard, which allows only one driver and up to 10 (assuming one unit load devices) receivers on each bus. RS -485 is a true multipoint standard, which allows up to 32 one unit load devices (any combination of drivers and receivers) on each bus. To allow for multipoint operation, the RS -485 specification requires that drivers must handle bus contention without sustaining any damage. Another important advantage of RS -485 is the extended common mode range (CMR), which specifies that the driver outputs and receiver inputs withstand signals that range from +1 2V to -7V. RS-422 and RS -485 are intended for runs as long as 4000’, so the wide CMR is necessary to handle ground potential differences, as well as voltages induced in the cable by external fields. Receiver (Rx) Features TP8485E utilize a differential input receiver for maximum noise immunity and common mode rejection. Input sensitivity is better than ±200mV, as required by the RS-422 and RS-485 specifications. Rx outputs feature high drive levels (typically 25mA @ VOL = 1V) to ease the design of optically coupled isolated interfaces. Receiver input resistance of 100kΩ surpasses the RS-422 specification of 4kΩ, and is eight times the RS-485 “Unit Load (UL)” requirement of 12kΩ minimum. Thus, these products are known as “one-eighth UL” transceivers, and there can be up to 256 of these devices on a network while still complying with the RS-485 loading specification. Rx 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. All the receivers include a “full fail-safe” function that guarantees a high level receiver output if the receiver inputs are unconnected (floating), shorted together, or connected to a terminated bus with all the transmitters disabled. Receivers easily meet the data rates supported by the corresponding driver, and all receiver outputs are three-stable via the active low RE input. Driver (Tx) Features TP8485E driver is a differential output device that delivers at least 2.5V across a 54Ω load (RS-485), and at least 2.8V across a 100Ω load (RS-422). The drivers feature low propagation delay skew to maximize bit width, and to minimize EMI, and all drivers are three- stable via the active high DE input. Full Fail-Safe All the receivers include a “full fail -safe” function that guarantees a high level receiver output if the receiver inputs are unconnected (floating), shorted together, or connected to a terminated bus with all the transmitters disabled. Receivers easily meet the data rates supported by the corresponding driver, and all receiver outputs are three-statable via the active low RE input. Hot Plug Function When a piece of equipment powers up, there is a period of time where the processor or ASIC driving the RS -485 control lines (DE, RE) is unable to ensure that the RS-485 Tx and Rx outputs are kept disabled. If the equipment is connected to the bus, a driver activating prematurely during power -up may crash the bus. To avoid this scenario, the TP8485E devices incorporate a “Hot Plug” function. Circuitry monitoring VCC ensures that, during power-up and power-down, the Tx and Rx outputs remain disabled, regardless of the state of DE and RE, if VCC is less than ~2.5V. This gives the processor/ASIC a chance to stabilize and drive the RS-485 control lines to the proper states.

Table 1. Bill of Materials Figure 12. Transient Protections Against ESD, EFT, and Surge Transients

± 12K ESD Protection, Full Fail-Safe RS-485 Transceiver www.3peak.com Rev. E.1 D b E e θ C Package Outline Dimensions SO-8 (SOIC-8) Symbol Dimensions In Millimeters Dimensions In Inches Min Max Min Max A1 0.100 0.250 0.004 0.010 A2 1.350 1.550 0.053 0.061 b 0.330 0.510 0.013 0.020 C 0.190 0.250 0.007 0.010 D 4.780 5.000 0.188 0.197 E 3.800 4.000 0.150 0.157 E1 5.800 6.300 0.228 0.248 e 1.270 TYP 0.050 TYP L1 0.400 1.270 0.016 0.050 θ 0° 8° 0° 8°

16 Rev. E.1 www.3peak.com TP8485E ± 12K ESD Protection, Full Fail-Safe RS-485 Transceiver Package Outline Dimensions MSOP-8 Symbol Dimensions In Millimeters Dimensions In Inches Min Max Min Max A 0.800 1.200 0.031 0.047 A1 0.000 0.200 0.000 0.008 A2 0.760 0.970 0.030 0.038 b 0.30 TYP 0.012 TYP C 0.15 TYP 0.006 TYP D 2.900 3.100 0.114 0.122 e 0.65 TYP 0.026 E 2.900 3.100 0.114 0.122 E1 4.700 5.100 0.185 0.201 L1 0.410 0.650 0.016 0.026 θ 0° 6° 0° 6° e E A D L1 L2 L R θ b

± 12K ESD Protection, Full Fail-Safe RS-485 Transceiver www.3peak.com Rev. E.1 IMPORTANT NOTICE AND DISCLAIMER Copyright© 3PEAK 2012-2023. All rights reserved. Trademarks. Any of the 思瑞浦 or 3PEAK trade names, trademarks, graphic marks, and domain names contained in this document /material are the property of 3PEAK. You may NOT reproduce, modify, publish, transmit or distribute any Trademark without the prior written consent of 3PEAK. Performance Information. Performance tests or performance range contained in this document/material are either results of design simulation or actual tests conducted under designated testing environment. Any variation in testing environment or simulation environment, including but not limited to testing method, testing process or testing temperature, may affect actual performance of the product. Disclaimer. 3PEAK provides technical and reliability data (including data sheets), design resources (including reference designs), application or other design recommendations, networking tools, security information and other resources "As Is". 3PEAK makes no warranty as to the absence of defects, and makes no warranties of any kind, express or implied, including without limitation, implied warranties as to merchantability, fitness for a particular purpose or non-infringement of any third-party’s intellectual property rights. Unless otherwise specified in writing, products supplied by 3PEAK are not designed to be used in any life-threatening scenarios, including critical medical applications, automotive safety-critical systems, aviation, aerospace, or any situations where failure could result in bodily harm, loss of life, or significant property damage. 3PEAK disclaims all liability for any such unauthorized use.