Datasheet

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General Description

The MAX3465–MAX3469 are high-speed differential

bus transceivers for RS-485 and RS-422 communica-

tions. They are designed to meet TIA/EIA-422-B,

TIA/EIA-485-A, V.11, and X.27 standards. The trans-

ceiver complies with the Profibus specification provid-

ing +2.1V minimum output level with a 54Ω load,

40Mbps data rate, and output skew less than 2ns. Each

part contains one three-state differential line driver and

one differential input line receiver. The devices operate

from a +5V supply and feature true fail-safe circuitry,

which guarantees a logic-high receiver output when the

receiver inputs are open or shorted. This enables all

receiver outputs on a terminated bus to output logic

highs when all transmitters are disabled.

All devices feature a 1/4-standard-unit load receiver

input impedance that allows 128 transceivers on the

bus. Driver and receiver propagation delays are guar-

anteed under 20ns for multidrop, clock distribution

applications. Drivers are short-circuit current limited

and are protected against excessive power dissipation

by thermal-shutdown circuitry. The driver and receiver

feature active-high and active-low enables, respective-

ly, that can be connected together externally to serve

as a direction control.

Applications

High-Speed RS-485 Communications

High-Speed RS-422 Communications

Level Translators

Industrial-Control Local Area Networks

Profibus Applications

Features

♦ Recommended for Profibus Applications

♦ Up to 40Mbps Data Rate

♦ 15ns Transmitter Propagation Delay

♦ 20ns Receiver Propagation Delay

♦ 2ns Transmitter and Receiver Skew

♦ High Differential Driver Output Level (2.1V on 54Ω)

♦ Hot-Swap Versions

♦ 1µA Shutdown Supply Current

♦ Low Supply Current Requirements (2.5mA, typ)

♦ Allow Up to 128 Transceivers on the Bus

♦ True Fail-Safe Receiver while Maintaining EIA/TIA-

485 Compatibility

♦ Designed for Multipoint Transmissions on Long

or Noisy Bus Lines

♦ Full-Duplex and Half-Duplex Versions Available

♦ Phase Controls to Correct for Twisted-Pair

Reversal for 14-Pin Versions

♦ Current-Limiting and Thermal Shutdown for

Driver Overload Protection

MAX3465–MAX3469

+5V, Fail-Safe, 40Mbps, Profibus RS-485/

RS-422 Transceivers

Ordering Information

PART

NUMBER

HALF/FULL

DUPLEX

RECEIVER/

DRIVER

ENABLE

LOW-

POWER

SHUTDOWN

HOT SWAP

RECEIVER/

DRIVER PHASE

SELECT

INDEPENDENT

SHDN PIN

PIN COUNT

MAX3465 Full Yes Yes Yes Yes Yes 14

MAX3466 Full Yes Yes No Yes Yes 14

MAX3467 Full No No No No No 8

MAX3468 Half Yes Yes Yes No No 8

MAX3469 Half Yes Yes No No No 8

Selector Guide

19-3038; Rev 3; 5/12

For pricing, delivery, and ordering information, please contact Maxim Direct

at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

Ordering Information continued at end of data sheet.

PART TEMP RANGE PIN-PACKAGE

MAX3465CSD 0°C to +70°C 14 SO

MAX3465CPD 0°C to +70°C 14 Plastic DIP

MAX3465ESD -40°C to +85°C 14 SO

MAX3465EPD -40°C to +85°C 14 Plastic DIP

Pin Configurations appear at end of data sheet.

Devices are also available in a lead(Pb)-free/RoHS-compliant

package. Specify lead-free by adding “+” to the part number

when ordering.

Summary of content (13 pages)

PAGE 1
9-3038; Rev 3; 5/12 +5V, Fail-Safe, 40Mbps, Profibus RS-485/ RS-422 Transceivers The MAX3465–MAX3469 are high-speed differential bus transceivers for RS-485 and RS-422 communications. They are designed to meet TIA/EIA-422-B, TIA/EIA-485-A, V.11, and X.27 standards. The transceiver complies with the Profibus specification providing +2.1V minimum output level with a 54Ω load, 40Mbps data rate, and output skew less than 2ns.
PAGE 2
MAX3465–MAX3469 +5V, Fail-Safe, 40Mbps, Profibus RS-485/ RS-422 Transceivers ABSOLUTE MAXIMUM RATINGS Supply Voltage (VCC) to GND ..................................-0.3V to +6V Control Input Voltage (RE, DE, DI, SHDN, TXP, RXP) to GND....................................................-0.3V to (VCC + 0.3V) Driver Output Voltage (Y, Z) to GND .........................-8V to +13V Receiver Input Voltage (A, B) to GND.......................-8V to +13V Differential Driver Output Voltage (Y - Z) ................
PAGE 3
+5V, Fail-Safe, 40Mbps, Profibus RS-485/ RS-422 Transceivers (VCC = +5V ±5%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS -200 -125 -50 mV Receiver Differential Threshold Voltage VTH -7V ≤ VCM ≤ +12V Receiver Input Hysteresis ΔVTH VCM = 0 Receiver Output High Voltage VOH IO = -4mA, VA - VB = VTH Receiver Output Low Voltage VOL IO = 4mA, VB - VA = VTH 0.
PAGE 4
ELECTRICAL CHARACTERISTICS (continued) (VCC = +5V ±5%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA = +25°C.
PAGE 5
+5V, Fail-Safe, 40Mbps, Profibus RS-485/ RS-422 Transceivers RECEIVER OUTPUT LOW VOLTAGE vs. TEMPERATURE 200 150 100 50 0 -15 10 35 60 150 125 100 75 4.90 4.80 4.75 4.70 4.65 4.60 -40 -15 10 35 60 85 -40 -15 10 35 60 85 TEMPERATURE (°C) TEMPERATURE (°C) RECEIVER PROPAGATION DELAY vs. TEMPERATURE DRIVER PROPAGATION DELAY vs. TEMPERATURE DRIVER DIFFERENTIAL OUTPUT VOLTAGE vs. TEMPERATURE 12 10 RDIFF = 54Ω OUTPUT VOLTAGE (V) 10 8 10 35 60 3.0 2.5 6 2.
PAGE 6
MAX3465–MAX3469 +5V, Fail-Safe, 40Mbps, Profibus RS-485/ RS-422 Transceivers Typical Operating Characteristics (continued) (VCC = +5V, TA = +25°C, unless otherwise noted.
PAGE 7
+5V, Fail-Safe, 40Mbps, Profibus RS-485/ RS-422 Transceivers MAX3465/MAX3466 MAX3467 TRANSMITTING TRANSMITTING INPUTS OUTPUTS INPUT OUTPUTS RE DE DI SHDN Z Y DI Z Y X 1 1 0 0 1 1 0 1 X 1 0 0 1 0 0 1 0 0 0 X 0 High-Z High-Z 1 0 X X Shutdown X X X 1 Shutdown RECEIVING OUTPUT A-B RO ≥ -0.05V 1 OUTPUT ≤ -0.2V 0 Open/Shorted 1 RECEIVING INPUTS INPUTS RE DE A-B SHDN RO 0 X ≥ -0.05V 0 1 0 X ≤ -0.
PAGE 8
MAX3465–MAX3469 +5V, Fail-Safe, 40Mbps, Profibus RS-485/ RS-422 Transceivers Pin Configurations and Typical Operating Circuit VCC DE TOP VIEW 4 SHDN 1 VCC RE 0.1μF 14 14 VCC 13 RXP RO 2 RE 3 12 A DE 4 11 B R DI 5 9 DI 5 D GND 6 9 GND 7 8 Y TXP Y Rt 10 RO R Z A 12 10 Z D MAX3465 MAX3466 RO TXP RXP 2 R 8 Rt 11 D DI B 13 3 6, 7 GND DIP/SO RE DE GND Figure 1. MAX3465/MAX3466 Pin Configuration and Typical Full-Duplex Operating Circuit 0.
PAGE 9
+5V, Fail-Safe, 40Mbps, Profibus RS-485/ RS-422 Transceivers The MAX3465–MAX3469 high-speed transceivers for RS-485/RS-422 communication contain one driver and one receiver. These devices feature true fail-safe circuitry, which guarantees a logic-high receiver output when the receiver inputs are open or shorted, or when they are connected to a terminated transmission line with all drivers disabled (see the True Fail-Safe section). The MAX3465–MAX3469’s driver slew rates allow transmit speeds up to 40Mbps.
PAGE 10
MAX3465–MAX3469 +5V, Fail-Safe, 40Mbps, Profibus RS-485/ RS-422 Transceivers 3V Y DE 1.5V 1.5V 0V R tLZ tZL(SHDN), tZL VOD Y, Z R 50% VOL VOC Z VOL + 0.5V OUTPUT NORMALLY LOW OUTPUT NORMALLY HIGH Y, Z 50% VOH - 0.5V 0V tHZ tZH(SHDN), tZH Figure 5. Driver DC Test Load Figure 9. Driver Enable and Disable Times 3V DE DI Y VID RDIFF CL f = 1MHz, tR ≤ 3ns, tF ≤ 3ns Z VOH RO 1.5V 1V A -1V B 1.5V OUTPUT VOL tPHL tPLH INPUT Figure 6. Driver Timing Test Circuit Figure 10.
PAGE 11
+5V, Fail-Safe, 40Mbps, Profibus RS-485/ RS-422 Transceivers B ATE R VID RECEIVER OUTPUT A Figure 12. Receiver Propagation Delay Test Circuit Applications Information 128 Transceivers on the Bus The standard RS-485 receiver input impedance is 12kΩ (one unit load), and the standard driver can drive up to 32 unit loads. The MAX3465–MAX3469 family of transceivers has a 1/4-unit-load receiver input impedance (48kΩ), allowing up to 128 transceivers to be connected in parallel on one communication line.
PAGE 12
MAX3465–MAX3469 +5V, Fail-Safe, 40Mbps, Profibus RS-485/ RS-422 Transceivers 120Ω 120Ω B DI B DE D D DE A B A B A DI A R RO R RO RE RE MAX3468 MAX3469 (HALF-DUPLEX) R R D D DI DE RO DI RE DE RO RE Figure 13.
PAGE 13
+5V, Fail-Safe, 40Mbps, Profibus RS-485/ RS-422 Transceivers REVISION NUMBER REVISION DATE 0 10/09 1 1/04 2 3 DESCRIPTION PAGES CHANGED Initial release. — Updated the description for the DE pin in the Pin Description table. 6 8/09 Replaced TOC 11. 5 5/12 Added lead-free compliant packaging information, updated Figure 3 caption, updated package table 1, 8, 11, 12 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product.