Rainbow Electronics ATR1841 User Manual

Features

• 405 nm, 650 nm and 780 nm Wavelengths Supported

• Blu-ray/HD-DVD x5, CD-R/RW x52, DVD-R/RW x16

• Adjustment of Mode and Gain by Setting Internal Register via Two-wire Interface (TWI)

• 200 MHz Channel Bandwidth

• Paraphase Outputs

• Internal Reference Voltage Generation

• Fast Settling Time

• Low Offset Voltage

• Power-down Mode

• Pb-free Optical 12-pin Package

Front Monitor
Diode for

Applications

• Blu-ray/HD-DVD

• DVD+RW with CD-RW Capability

• DVD-RW with CD-RW Capability

• DVD-RAM with CD-RW Capability

• Recordable Optical Data Storage Devices

1. Description

The ATR1841 is a front monitor diode (FMD) which controls the laser power of the
optical pickup for Blu-ray/HD-DVD, DVD and CD drives in one IC.

With the Two-wire Interface (TWI) it is possible to fit the laser power for
Blu-ray/HD-DVD, DVD and CD. Two bits are used to set the mode/gain level and 6
additional bits are used for gain trimming, within ±6 dB. Entering sleep mode is also
controlled via the TWI.

The integrated PIN diode and the high speed amplifier with low output impedance
ensures stable driver performance.

All output channels are set to tri-state during sleep mode.

Due to its small package size the ATR1841 is especially suited for applications with
low height requirements like SLIM and Ultra-SLIM drives.

Blu-ray/HD-DVD/
DVD/CD with
TWI

ATR1841

Summary

Preliminary

NOTE: This is a summary document.

The complete document is currently not
available. For more information, please
contact your local Atmel sales office.

9103AS–DVD–08/07

Figure 1-1. Block Diagram

SDA

SCL

VCC

Gain Select (H/M/L)
Gain Adjust (±6 dB)

GND

RF+

RF-

Internal

Vref

ADS

2

ATR1841 [Preliminary]

9103AS–DVD–08/07

2. Pin Configuration

Figure 2-1. Pinning QFN12L

ATR1841 [Preliminary]

NC NC

10 11

GND

RF-

RF+

VCC

Table 2-1. Pin Description

Pin Symbol Type Function

1 GND Supply Ground
2 RF- Analog Negative output
3 RF+ Analog Positive output
4 VCC Supply Power supply
5SDADigital
6 SCL Digital
7ADSAnalog
8 GND Supply Ground

9 NC Not connected
10 NC Not connected
11 NC Not connected
12 NC Not connected

TWI serial data
TWI serial clock
TWI slave address select

1

2

3

4

912

NC NC

GND

8

ADS

7

SCL

6

SDA

5

9103AS–DVD–08/07

3