PRELIMINARY
SP8126B
High Speed Differential APC Amplifier
FEATURES
■ Dual Wavelength
■ Slew Rate of 300V/µs
■ Fast Settling Time - 7ns
■ Gain Control
■ 2V Output Swing
■ Low Offset Voltage: < 10mV
■ Low Offset Drift: < 20µV/°C
■ 12dB External Gain Adjust Range
VCC 1
GAIN 2
RGCOM 3
GND 4
SP8126B
8 Pin COB
8 VOUT +
7 VOUT -
6 RGAIN2
5 RGAIN1
APPLICATIONS
■ DVDRW
■ DVDRAM
■ CDRW
DESCRIPTION
The SP8126B is a high-speed, differential output APC amplifier that integrates the photodiode
and adjustable gain block on one chip. Independent gain control allows individual adjustment for
780mn and 650nm wavelength operation, as found in CD/DVD optical storage drives. This allows
the user to control the laser power of the system in high-speed DVDRW, DVDRAM and CDRW
systems. The wide 2V output swing also allows better system performance, through improved
dynamic range.
VCC
GND
-
TIA
+
GAIN
Gain Control
+
Buffer
-
R1
R3
500
500
R2
500
-
Buffer
+
RGCOM
RGAIN1
RG1
RGAIN2
RG2
Figure 1. SP8126B Functional Diagram and Typical Application
Rev:B Date: 3/18/04
SP8126B High Speed Differential APC Amplifier
1
VOUT+
1VP-P
50pF 1k
(Depend
on FPC)
(Flexible Flat Cable)
VOUT-
1VP-P
50pF 1k
© Copyright 2004 Sipex Corporation