OUT+

OUT−

VCC

GND

Bandgap Voltage

Reference and

Bias Current

Generation

Offset

Cancellation

CML

Output

Buffer

+

−

+

−

IN

FILTER

RSSI

Voltage

Amplifier

Transimpedance

Amplifier

Disable

750 W

Not Recommended for New Designs

ONET2511TA

www.ti.com

SLLS622 – SEPTEMBER 2004

2.5 GBPS TRANSIMPEDANCE AMPLIFIER WITH RSSI

Check for Samples: ONET2511TA

1

FEATURES

DESCRIPTION

•

2.5 GHz Bandwidth

•

4.0 k

Ω Differential Transimpedance

The ONET2511TA is a high-speed transimpedance

amplifier used in SDH/SONET systems with data

•

10 pA/

√Hz Typical Input Referred Noise

rates up to 2.5Gbps. It features a low input referred

•

2 mA Maximum Input Current

noise, 2.5GHz bandwidth, 4.0k

Ω transimpedance,

•

Offset Cancellation

and a received signal strength indicator.

•

Received Signal Strength Indication

The ONET2511TA device is available in die form and

•

Differential CML Data Outputs

requires a single +3.3V supply. It is very power

efficient and dissipates less than 83 mW (typical). It is

•

Single +3.3V Supply

characterized for operations from –40°C to 85°C.

•

Bare-Die Option

AVAILABLE OPTIONS

APPLICATIONS

DIE

•

SONET OC-48

–40°C to 85°C

ONET2511TAY

•

SDH STM-16

•

APD Preamplifier-Receivers

•

PIN Preamplifier-Receivers

DETAILED DESCRIPTION

BLOCK DIAGRAM

The ONET2511TA is a high performance 2.5 Gbps transimpedance amplifier that can be segmented into the

signal path, filter, and offset cancellation block.

The signal path consists of a transimpedance amplifier stage, a voltage amplifier, and an output buffer.

The filter circuit provides a filtered VCC for the photodiode.

The offset correction circuit uses an internal low pass filter to cancel the DC on the input and it provides a signal

to monitor the received signal strength.

A simplified block diagram of the ONET2511TA is shown in Figure 1.

Figure 1. Simplified Block Diagram of the ONET2511TA

1

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas

Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

PRODUCTION DATA information is current as of publication date.

Copyright © 2004, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.