LT1137A

Features:

ESD Protection over ±10kV
Uses Small Capacitors: 0.1F, 0.2F
1A Supply Current in SHUTDOWN
Pin Compatible with LT1137
Operates to 120k Baud
CMOS Comparable Low Power: 60mW
Operates from a Single 5V Supply
Easy PC Layout: Flowthrough Architecture
Rugged Bipolar Design
Outputs Assume a High Impedance State When Off or Powered Down
Improved Protection: RS232 I/O Lines Can Be Forced to ±30V without Damage
Output Overvoltage Does Not Force Current Back into Supplies
Absolutely No Latch-up
Available in SO Package


Application

Notebook Computers
Palmtop Computers


Pinout




Specifications

Supply Voltage (V_CC) ................................................ 6V
V⁺ ............................................................................. 13.2V
V (Note 7) .............................................................. 6.5V
Input Voltage
  Driver ..................................................................... V to V+
  Receiver ................................................................. 30V to 30V
Output Voltage
  Driver ..................................................................... 30V to 30V
  Receiver ................................................................. 0.3V to V_CC + 0.3V
Short Circuit Duration
  V⁺ .......................................................................... 30 sec
  V .......................................................................... 30 sec
  Driver Output ......................................................... Indefinite
  Receiver Output ..................................................... Indefinite
Operating Temperature Range
  LT1137AC............................................................... 0°C to 70°C
  LT1137AI................................................................ 40°C to 85°C
Storage Temperature Range ................................... 65°C to 150°C
Lead Temperature (Soldering, 10 sec)..................... 300°C


Description

The LT1137A is a three-driver, five-receiver RS232 transceiver, pin compatible with the LT1137, offering performance improvements and two SHUTDOWN modes. The LT1137A's charge pump is designed for extended compliance, and can deliver over 40mA of load current. Supply current is typically 12mA, competitive with similar CMOS devices. An advanced driver output stage operates up to 120k baud while driving heavy capacitive loads.

The LT1137A is fully compliant with all EIA-RS232 specifications. Special bipolar construction techniques protect the drivers and receivers beyond the fault conditions stipulated for RS232. Driver outputs and receiver inputs can be shorted to ±30V without damaging the device or the power supply generator. In addition, the RS232 I/O pins are resilient to multiple ±10kV ESD strikes.

The transceiver LT1137A has two SHUTDOWN modes. One mode disables the drivers and the charge pump, the other shuts down all circuitry. While shut down, the drivers and receivers assume high impedance output states.