AK2571 Datasheet, PDF (22/52 Pages) Asahi Kasei Microsystems – Single-Chip Automatic Power/Temperature Control for WDM Laser Diodes

AKM Confidential
AK2571
5. Sequencer
5.1 Operation mode
The AK2571 has three operation modes shown below. Use the serial interface to change from one mode to another. Figure
5-1 shows the operating flowchart and table 5-1 indicates the circuit block capabilities.
1) Self-operation mode: Operates ATC and APC automatically according to the data stored in EEPROM.
2) Register access mode: Adjust the data to set the characteristics of LD. Read and write registers are accessed by writing
commands to the Digital interface.
3) EEPROM access mode: Fix the adjusted data and parameters in EEPROM. Data in register are written in
EEPROM and reset. All ATC and APC functions are disabled in this mode.
Figure 5-1
POWER ON
Register
RST
access
mode
Self
Retain the
operation value of
mode
Register
RST
RST
EEPROM
RST
access
mode
Table 5-1
Register
EEPROM
Status
APC
ATC
Read
Write
Read
Write
P_EEP
Self operation mode Register access
EEPROM access
O.K.
O.K.
Non
Non
O.K.
Non
Non
Non
O.K.
Non
Non
O.K.
0
0
1
Auto operation by Operation by register Shut Down
EEPROM data
data
Auto operation by Auto operation by Shut Down
EEPROM data
register data
5.2 Self operation mode
5.2.1 Start up sequence
The AK2571 has various start-up sequence patterns that set the control register (R_CTRL_AKM / R_CTRL_USER). The
AK2571 automatically executes the start up sequence stored in EEPROM when it is started or re-start. Table 5-2 and
Figure 5-2explains each sequence.
<Rev. 0.6E Preliminary>
-22-
2001/11