G569C Datasheet, PDF (1/11 Pages) Global Mixed-mode Technology Inc – CD-RW Laser Diode Current Driver

Global Mixed-mode Technology Inc.
G569C
CD-RW Laser Diode Current Driver
Features
„ Single +5V supply
„ Laser diode read current driver
„ Laser diode write current driver
„ Laser diode Erase current driver
„ Deltap circuit to control write current
„ FSA circuit to integrate photo diode current
„ Cagain circuit to convert V_cagain into current
„ Dalpha circuit to perform voltage subtraction
and limiting
„ 3-wire interface to control internal DAC
„ A build-in OP-AMP
„ 48-pin SSOP package
Applications
„ CD-RW Drive
General Description
The G569C is a single chip solution for the various
functions relating to laser diode operation in a CD-RW
drive. The G569C integrates nine functional blocks in
one chip. It has five voltage-to-current converters, one
current-to-voltage converters which is called FSA, one
OP-AMP, one eight-channels D/A converter, and one
voltage subtracter with output clamping capability
called Dalpha.
Three of the five V-to-I converters provide the laser
diode currents for Read, Write, and Erase operations,
respectively; another one of the V-I converters
provides the Cagain current; and the other one
provides Deltap current which can selectively shunt a
certain amount of laser diode current for write
operation. For the Write and Erase operations, the
voltage to current conversion ratio can be adjusted
using an external or internal DAC resistor array. The
FSA circuit performs integration on the output current
of an external photo diode, and sample-and-hold the
peak voltage. It is used to monitor the laser diode
power. The internal eight-channel D/A converter is
used to provide the input voltage for above functional
blocks. The G569C is available in a 48-pin SSOP
surface-mount package.
Pin configuration
IW_IN 1
LS_DELTA 2
TST1 3
PWO 4
DALPHA 5
PWO_I 6
PWB 7
PWMAX 8
PWMIN 9
/RESET 10
VSS 11
EDB 12
LS_ERASE 13
PERASE 14
RECORD 15
CDR 16
S2V9 17
CAGAIN2 18
CAGS_I 19
DCAGAIN 20
CAGAIN ²¹
RCAGAIN1 22
RCAGAIN2 23
PRFINE 24
G569C
SSOP-48
Ver: 1.0
Oct 02, 2000
48 WDB
47 _{LS_WRITE}
46 PWRITE
45 LD
44 DI
43 CLK
42 VSS
41 VOUT
40 VI-
39 _VI+
38 VDD
37 FSOF
36 FSWS
35 _FSCLR
34 _FSW
33 _IFSA
32 _FSR
31 _FSRS
30 _VDD
29 _{SELN4_IN}
28 PR_I
27 LS_READ
26 IR
25 PRCOARSE
Ordering Information
ORDER ORDER NUMBER
NUMBER
(Pb free)
TEMP.
RANGE
PACKAGE
G569CS8U G569CS8Uf 0°C to 85°C SSOP-48
Note: S8: SSOP-48
U: Tape & Reel
TEL: [phone]
http://www.gmt.com.tw
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