T0800-PJQ
| Model | T0800-PJQ |
| Description | 5-CHANNEL LASER DRIVER WITH RF OSCILLATOR AND 2 OUTPUTS |
| PDF file | Total 14 pages (File size: 291K) |
| Chip Manufacturer | ATMEL |
Features
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Current-controlled Output Current Source with 5 Input Channels
2 Selectable Outputs for Grounded Laser Diodes
Output Current per Channel up to 200 mA
Total Output Current up to 250 mA
Rise Time 1.0 ns/Fall Time 1.1 ns
On-chip RF Oscillator
Control of 2 Different Frequencies and Swings by Use of 4 External Resistors
Oscillator Frequency Range from 200 MHz to 600 MHz
Oscillator Swing to 100 mA
Single 5-V Power Supply
Common Enable/Disable Input
TTL/CMOS Control Signals
Small SSO24 Package and QFN28 Package
5-Channel Laser
Driver with RF
Oscillator and
2 Outputs
T0800
Applications
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Combo Drives (DVD + CD-RW)
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DVD-RAM with CD-RW Capability
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DVD-RW with CD-RW Capability
1. Description
The T0800 is a laser diode driver for the operation of two different, grounded laser
diodes for DVD-RAM (650 nm) and CD-RW (780 nm). It includes five channels for five
different optical power levels which are controlled by a separate IC. The read channel
generates a continuous output level. The channels 2 to 5 are provided as write chan-
nels with very fast switching speeds. When a
low
signal is applied to the NE pins, write
current pulses are enabled. All channels are summed together and switched to one of
the two outputs IOUTA or IOUTB by the select input SELA. Each channel can contrib-
ute up to 200 mA to the total output current of up to 250 mA. A total gain of 100 is
provided between each reference current input and the selected output. Although the
reference inputs are current inputs, voltage control is possible by using external resis-
tors. An on-chip RF oscillator reduces laser mode hopping noise during read mode.
Frequency and swing can be set independently for the two selectable outputs with two
pairs of resistors. Oscillation is enabled by a
high
signal at the ENOSC pin. Complete
output current and oscillator switch-off is achieved by a
low
signal at the ENABLE
input.
Rev. 4503D–DVD–02/05
