V6601 RS-485 Transceiver

Transcription

1 V6601 RS-485 Transceiver Version: 0.3 Release Date: January 19, 2018 Specifications are subject to change without notice This document contains information that is proprietary to Unauthorized reproduction of this information in whole or in part is strictly prohibited.

2 Revision History Date Version Description Initial release Updated power consumption in shutdown mode to 1μ Updated power supply to 5V Updated data rate <500Kbps Updated data rate <20Kbps dd absolute maximum ratings - 1 -

3 General Description The V6601 is an RS-485 transceiver featuring half-duplex, low power consumption, low slewrate and is completelycompliant with the EI/TI-485 standard. The V6601 integrates one driver and one receiver, both can be enabled independently. When both driver and receiver are disabled, the device will output the high impedance (Tri-State). The V6601 has high driving capability allowing up to 256 transmitters on the same communication bus. The low-slew-rate driver can reduce EMI and reflections caused by inappropriate terminal matching. The V6601 can support the high-speed communication. The maximum communication speed is 20Kbps.In the application of 5V power supply, the input/output logic level is 5V. The V6601,with built-in pull-up and pull-down resistors,be ofthe 0.5-m supply current underthe no-load condition. In the shutdown mode, the power consumption is less than 1μ. The V6601 is protected from faults due to shorted or open receiver input, over-temperature, over-current, and over-voltage protection. Features Supply voltage range: 5V Half-duplex mode Data rate: <20Kbps High driving capability: Up to 256 transmitters on one bus Differential driver output: 1.3V VOD ESD protection: ± 15kV Human ody Model (HM) Fail-safe receiver Over-temperature, over-current, and over-voltage protection Polarity detection and adaption Low-slew-rate driver to minimize EMI and reduce reflections caused by inappropriate terminal matching Operation temperature: -40 C ~+85 C Package: SOP-8 pplications Utility meters Industrial control - 2 -

4 Table of Contents Revision History... 1 General Description... 2 Features... 2 pplications... 2 Table of Contents... 3 Figure List... 4 Table List Pin Descriptions Truth Table Specifications bsolute Maximum Ratings Electrical Characteristics Typical Operating Characteristics Test Circuits and Waveform Circuits Description Fail-Safe Protection Over-Temperature Protection Output Protection Polarity Detection and daption Up to 256 Drivers on One us Outline Dimensions

5 Figure List Figure4-1Differential Output Voltage vs. Temperature Figure4-2 Output Current (No Load) vs. Temperature Figure4-3 Receiver Propagation Delay Figure4-4 Receiver Output High Voltage vs. Temperature Figure4-5 Output Current vs. Driver Output Low Voltage Figure4-6 Driver Propagation Delay Figure5-1 Driver Test Circuits Figure5-2 Driver Propagation Delay Waveform Figure5-3 Receiver Propagation Delay Test Circuit and Waveform Figure6-1RS-485 Network with V

6 Table List Table 2-1Transmitting... 7 Table 2-2 Receiving

7 Polarity Detection and daption 1. Pin Descriptions RO 1 R 8 V CC RE 2 7 DE 3 6 DI 4 D 5 GND No. Pin Description Receiver output. 1 RO When RE is logic low, and (-)>-10mV, RO is logic high. When RE is logic low, and (-)<-80mV, RO is logic low. When RE is logic low, and the receiver inputs are shorted or open, RO is guaranteed to be logic high. Receiver output enable. 2 RE When RE is logic low, RO is active. When RE is logic high, RO is in a high impedance state. When RE is logic high, and DE is logic low, the device enters low-power shutdown mode. Driver output enable. 3 DE When DE is logic high, the driver output is enabled. When DE is logic low, the driver output is in a high impedance state. When RE is logic high, and DE is logic low, the device enters low-power shutdown mode. Driver input. 4 DI When DE is logic high, logic low at DI enforces noninverting output low and inverting output high. When DE is logic high, logic high at DI enforces noninverting output high, and inverting output low. 5 GND Ground - 6 -

8 No. Pin Description 6 Receiver input/driver output 7 8 V CC Port and will be defined or redefined as noninverting or inverting according to the polarity detection. Positive supply input: 4.5V V CC 5.5V V CC should be connected to a 0.1μF, and then connected to GND. 2. Truth Table Table 2-1Transmitting Input Output RE DE DI Inverting Output Noninverting Output X X Z Z 1 0 X Shutdown Table 2-2 Receiving Input Output RE DE - RO 0 X >-10mV 1 0 X <-80mV 0 0 X Open/shorted X X 1 Port and are defined or redefined as driver inverting output / driver noninverting output, according to the polarity detection. In the table, 1 represents logic high, 0 represents logic low, Z represents high impedance state, and X represents don t care

9 3. Specifications 3.1. bsolute Maximum Ratings Parameter Symbol Test Conditions Min. Max. Unit Supply Voltage V CC +6 V Control Input Voltage /RE, DE V Driver Input Voltage DI V Driver Output Voltage, V Receiver Input Voltage, V Receiver Output Voltage RO -0.3 V CC +0.3 V Continuous Power Dissipation T =+70 C, Derate 5.85 mw/ C above +70 C 471 mw Operating Temperature C Storage Temperature Range C Soldering temperature Sodering, 10s 300 C Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications are not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability Electrical Characteristics ll maximum/minimum specifications apply over the entire recommended operation range, unless otherwise noted. ll typical specifications are at T =25 C, V CC =5.0V unless otherwise noted. ll current into the device is positive, and all current out of the device is negative. ll voltages are relative to the respective ground. Parameter Symbol Test Conditions Min. Typ. Max. Unit Driver Supply Voltage Range V CC V R L =100Ω 3.5 V CC Driver Differential Outputs V OD R L =54Ω 2.88 V CC V No load V CC - 8 -

10 Parameter Symbol Test Conditions Min. Typ. Max. Unit Change in Magnitude of Differential Output Voltage 1 ΔV OD R L =100Ω or 54Ω 0.2 V Common-Mode Output Voltage V OC R L =100Ω or 54Ω V CC /2 V Change in Magnitude of Common-Mode Output Voltage ΔV OC R L =100Ω or 54Ω 0.2 V Input Threshold High V IH DE,DI,RE 2.0 V Input Threshold Low V IL DE,DI,RE 0.8 V Input Hysteresis V HYS DE,DI,RE 100 mv Driver Short-Circuit Output Current 2 I OSD 0 V OUT +12V V V OUT V CC m Driver Short-Circuit Foldback Output Current I OSDF (V CC -1) V OUT +12V 30-7V V OUT +1V -30 m Thermal-Shutdown Threshold T TS 150 C Thermal-Shutdown Hysteresis T TSH 30 C DE=GND V IN = Input Current I, V CC =GND or V CC V IN =-7-60 μ Receiver Receiver Differential Threshold Voltage V TH -7V V OUT 12V mv Receiver Input Hysteresis ΔV TH 20 mv RO Threshold High V OH I O =-5m V CC V RO Threshold Low V OL I O =5m 0.3 V Three-State Output Current at Receiver I ORZ 0 V O V CC ±1 μ Receiver Input Impedance R IN -7V V CM 12V 180 kω Internal Resistance Pull-Up/Pull-Down R IS -7V V CM 12V 20 kω 1 Δ V OD denotes the change in magnitude of V OD, and Δ V OC denotes the change in magnitude of V OC, when the DI input changes state. 2 The driver short-circuit output current denotes the peak current just prior to the foldback current limiting. The short-circuit foldback output current denotes the current hysteresis to allow a recovery from bus contention

11 Parameter Symbol Test Conditions Min. Typ. Max. Unit Receiver Short-Circuit Output Current I OSR 0 V RO V CC m Supply Current No load, RE =DE=V CC DI= V CC m DI= m Supply Current I CC No load, RE =0, DE=V CC DI= V CC m DI= m No load, RE =DE=0 DI=0/ V CC m Supply Current in Low-Power Shutdown Mode I SHDN RE =V CC, DE=0 1 μ Driver Switching Characteristics Propagation Delay Driver Differential Output Rise or Fall Time t DPLH ns R DIFF =54Ω, C L =50pF t DPHL ns ns Maximum Data Rate F MX 20 kbps Receiver Switching Characteristics t RPLH V -V 2.0V ns Propagation Delay t RPHL Rise or fall time is less than 15ns ns V -V 2.0V Receiver Input Rise or Fall Time t RSKD Rise or fall time is less than 15ns 5 10 ns Maximum Data Rate F MX 20 kbps Temperature Operation Temperature T C Storage Temperature T S C Lead Temperature (Soldering, 10s) 300 C

12 Output Current (u) Differential Output Voltage (V) 4. Typical Operating Characteristics Driver Differential Output Voltage vs. Temperature Temperature ( ) R L =54Ω Figure4-1Differential Output Voltage vs. Temperature Output Current (No Load) vs. Temperature DE=RE=V CC, DI=0 DE=RE=0 DE=RE=V CC, DI=V CC No Load Temperature ( ) Figure4-2 Output Current (No Load) vs. Temperature

13 RO High Voltage (V) Receiver Propagation Delay No Load V -V 2V/div RO 2V/div 2.50µs/div Figure4-3 Receiver Propagation Delay RO High Voltage vs. Temperature Temperature ( ) I O =-5m Figure4-4 Receiver Output High Voltage vs. Temperature

14 Output Low Current (m) Output Current vs. Driver Output Low Voltage Output Low Voltage (V) Figure4-5 Output Current vs. Driver Output Low Voltage Driver Propagation Delay R L =54O DI 2V/div V -V 2V/div 2.50µs/div Figure4-6 Driver Propagation Delay

15 5. Test Circuits and Waveform V CC DE R L /2 DI D VOD R L C L VOD R L /2 VOC Driver DC Test Load Driver Timing Test Circuit Figure5-1 Driver Test Circuits V CC V CC /2 V CC /2 0V t DPLH t DPHL VOD VOD/2 +V OD 90% 90% -V OD 10% 10% t DR t DF Figure5-2 Driver Propagation Delay Waveform +1V 0V 0V TE VID R RO t RPLH t RPHL -1V V OH V CC /2 Test Circuit RO Waveform V OL Figure5-3 Receiver Propagation Delay Test Circuit and Waveform

16 6. Circuits Description The V6601 is an RS-485 transceiver featuring half-duplex, low power consumption, low slewrate and is completelycompliant with the EI/TI-485 standard. The V6601 integrates one driver and one receiver, both can be enabled independently. When both driver and receiver are disabled, the device will output the high impedance (Tri-State). The V6601 has high driving capability allowing up to 256 transmitters on the same communication bus. The low-slew-rate driver can reduce EMI and reflections caused by inappropriate terminal matching. The V6601 can support the high-speed communication. The maximum communication speed is over20kbps.in the application of 5V power supply, the input/output logic level is 5V. The V6601,with built-in pull-up and pull-down resistors,be ofthe 0.5-m supply current underthe no-load condition. In the shutdown mode, the power consumption is less than 1μ. The V6601 is protected from faults due to shorted or open receiver input, over-temperature, over-current, and over-voltage protection Fail-Safe Protection The V6601 has a fail-safe-protected receiver input. When the receiver input is shorted or open, or when all the drivers on the terminated cable are disabled, the device can guarantee the RO is logic high. In the device, the receiver differential threshold voltage is -10mV and -80mV. If the differential input of the receiver (-) is higher than -10mV, RO will be logic high. If all the drivers on the terminated cable are disabled, the differential input of the receiver (-) will be pulled down to 0V, and RO will be logic high. If the differential input of the receiver (-) is less than -80mV, RO will be logic low Over-Temperature Protection The integrated thermal shutdown circuit in the V6601 can protect the device from the power dissipation caused by faults. When the temperature of the device exceeds +150 C, the device goes to thermal shut-down mode Output Protection In the V6601, the overvoltage protection and foldback current limiting are intended to protect the device from overvoltage faults or excessive output current. The overvoltage protection circuit compares the output voltage of ports and all the time when both RE and DE are logic high. When V or V is less than GND, or V or V is higher than V CC, the device is in the overvoltage mode, and the circuit will protect the device from damage due to the overvoltage faults. In the low power shutdown mode, this circuit stops working. The foldback current limiting feature of the V6601 is designed to protect the output from being shorted. When powered on, 60ms later, the foldback current limiting circuit is enabled automatically. The

17 Polarity Detection and daption Polarity Detection and daption limiting threshold current is 100m, and the current hysteresis is 30m. When the output current is higher than 100m, most output transistors are disabled. When the circuit stops shorting, the output current falls, and all the transistors recover working. Typically, the short-circuit output current is 45m Polarity Detection and daption The embedded polarity detection and adaption circuit in the V6601 enables the device to detect, and define the polarity of both and ports continuously when the device works as a receiver. There are internal pull-up and pull-down resistors in the V6601, so, it is not necessary to connect resistors outside the device as done with traditional RS-485 transceivers. ut, in an RS-485 network including the V6601, it is recommended to connect a pull-up and a pull-down resistor outside the collector to define the polarity of the differential cable. The resistance should be no more than 15kΩ, usually 10kΩ. RO RE R D DI DE DE DI D V CC R RE RO Polarity Detection and daption R R R D Collector RO RE DE DI Figure6-1RS-485 Network with V Up to 256 Drivers on One us With regard to a standard RS-485 transceiver, the receiver input impedance is 12kΩ (1-unit load), and the driver can drive up to 32-unit loads. s for the V6601, the receiver input impedance is higher than 1/8-unit loads (R1>96kΩ), which allows up to 256 drivers on the bus.ll drivers can be connected to one bus in any combination only if the total loads are no more than 32 units. The receiver input resistor is paralleled to the internal pull-up and pull-down resistors, of which the total resistance is equal to the resistance of the receiver

18 6. Outline Dimensions 2 1 E1 θ3 θ4 D 3 E θ1 θ2 b b1 Section - c1 c h θ h L (L1) R1 R L2 Dimensions (Unit: mm) Symbol MIN NOM MX b b c c D E E e L SC L1 L2 R REF 0.25SC - - R h θ 0-8 θ θ θ θ e b