TZA3023T NXP Semiconductors, TZA3023T Datasheet - Page 5

• Manufacturer Part Number: TZA3023T
• Manufacturer: NXP Semiconductors

Specifications of TZA3023T

• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 8
• Lead Free Status / RoHS Status: Not Compliant

Philips Semiconductors
FUNCTIONAL DESCRIPTION
The TZA3023 is a transimpedance amplifier intended for
use in fibre optic links for signal recovery in STM4/OC12
applications. It amplifies the current generated by a photo
detector (PIN diode or avalanche photodiode) and
transforms it into a differential output voltage. The most
important characteristics of the TZA3023 are high receiver
sensitivity and wide dynamic range.
High receiver sensitivity is achieved by minimizing noise in
the transimpedance amplifier. The signal current
generated by a PIN diode can vary between
1 A to 1.5 mA (p-p). An AGC loop is implemented to
make it possible to handle such a wide dynamic range.
The AGC loop increases the dynamic range of the receiver
by reducing the feedback resistance of the preamplifier.
2002 Sep 05
handbook, full pagewidth
handbook, full pagewidth
SDH/SONET STM4/OC12
transimpedance amplifier
Fig.4 Logic level symbol definitions for data outputs OUT and OUTQ.
V O(max)
V CC
V O(min)
V OQH
V OQL
V OH
V OL
600
Fig.3 Data output buffer.
2 mA
CML/PECL OUTPUT
600
5
V OO
The AGC loop hold capacitor is integrated on-chip, so an
external capacitor is not needed for AGC. The AGC
voltage can be monitored at pad 13 on the bare die
(TZA3023U). Pad 13 is not bonded in the packaged device
(TZA3023T). This pad can be left unconnected during
normal operation. It can also be used to force an external
AGC voltage. If pad 13 is connected to GND, the internal
AGC loop is disabled and the receiver gain is at a
maximum. The maximum input current is then
approximately 50 A.
A differential amplifier converts the single-ended output of
the preamplifier to a differential output voltage (see Fig.3).
4.5 mA
4.5 mA
30
30
MGK922
MGK885
V o (p-p)
V CC
V OUTQ
V OUT
Product specification
TZA3023