1 Features

1• Extended VCC operating nodes: 1.8 V, 3.3 V, or

5.0 V

– Unique Tripler Charge Pump Architecture

Enables Low VCC of 1.8V While Maintaining

Compatibility with 3.3 V and 5 V Supplies

• Integrated Level-Shifting Functionality Eliminates

the Need for External Power or Additional Level

Shifter While Interfacing with Low-Voltage MCUs

• Enhanced ESD Protection on RIN Inputs and

DOUT Outputs

– ±15 kV IEC 61000-4-2 Air-Gap Discharge

– ±8 kV IEC 61000-4-2 Contact Discharge

– ±15 kV Human-Body Model

• Specified 1000-kbps Data Rate

• Auto Powerdown Plus Feature

• Low 0.5uA Shutdown Supply Current

• Meets or Exceeds Compatibility Requirements of

RS-232 Interface

• For 2.5 V Single Supply Applications, Consider

TRS3318E as an Optimized Solution

2 Applications

• Remote Radio Unit (RRU)

• Base Band Unit (BBU)

• Electronic Point of Sale (EPOS)

• Diagnostics & Data Transmission

• Battery-Powered Equipment

3 Description

The TRS3122E is a two-driver and two-receiver RS-

232 interface device, with split supply pins for mixedvoltage

operation. All RS-232 inputs and outputs are

protected to ±15 kV using the IEC 61000-4-2 Air-Gap

Discharge method, ±8 kV using the IEC 61000-4-2

Contact Discharge method, and ±15 kV using the

Human-Body Model.

The charge pump requires five small 0.1-μF

capacitors for operation from as low as a 1.8-V

supply. The TRS3122E is capable of running at data

rates up to 1000 kbps, while maintaining RS-232-

compatible output levels.

The TRS3122E has a unique VL pin that allows

operation in mixed-logic voltage systems. Both driver

in (DIN) and receiver out (ROUT) logic levels are pin

programmable through the VL pin. This eliminates the

need for additional voltage level shifter while

interfacing with low-voltage microcontrollers or

UARTs.

Auto Powerdown Plus automatically places the

device in a low power mode when the device has not

received or transmitted data for more than 30

seconds. This feature makes this device a very

attractive option for battery powered or other powersensitive

applications.