OQ2538U

Features:

· Differential 100 W outputs for direct connection to Current-Mode Logic (CML) inputs
· Wide bandwidth (3 GHz)
· 48.5 dB limiting gain
· Noise figure typically 11 dB
· Automatic offset compensation
· Input level-detection circuits for Automatic Gain Control (AGC) and Loss Of Signal (LOS) detection
· Low power dissipation (typically 270 mW)
· Single -4.5 V supply voltage
· Low cost LQFP48 plastic package.


Application

· Main amplifier in Synchronous Digital Hierarchy (SDH) and Synchronous Optical Network (SONET) systems for short, medium and long haul optical transmission
· Level detector for laser diode control loops
· Wideband RF gain block with internal level detectors.


Pinout




Specifications

SYMBOL	PARAMETER	CONDITIONS	MAX.	MAX.	UNIT
VEE	negative supply voltage		-6.0	+0.5	V
VI	input voltage difference	note 1	-600	+600	mV
IIN, IINQ	input current		-2.0	+2.0	mA
In	DC current pins 30 and 32 pins 3, 18, 19 and 43 pin 21 pins 44 and 45 pin 22		-6 -3 -2 -1 -0.1	+10 +3 +2 +1 +0.1	mA mA mA mA mA
Ptot	total power dissipation		-	380	mW
Tj	junction temperature		-	150
Tstg	storage temperature		-65	+150

Note
1. V_I = V_IN - V_INQ (AC only). The DC level is internally controlled.


Description

The OQ2538U is a limiting amplifier IC intended for use as the main amplifier in 2.5 Gbits/s Non-Return to Zero (NRZ) transmission systems (SDH/SONET).

Comprised of four amplifier stages with a total gain of 48.5 dB, OQ2538U provides for a wide input signal dynamic range at a constant CML-compatible output level.

Two level-detection circuits of OQ2538U are provided for monitoring AGC and LOS input signal levels. An internal automatic offset compensation circuit eliminates offset in the amplifier chain.