AK2574VB AKM [Asahi Kasei Microsystems], AK2574VB Datasheet - Page 27

• Manufacturer Part Number: AK2574VB
• Description: 156M Laser Diode Driver + APC for Burst Mode
• Manufacturer: AKM [Asahi Kasei Microsystems]

operation mode and Table 6-2 shows the command to change operation mode.
R_MODE. When set WP = “H”, access to R_MODE is prohibition.
The AK2574 operation modes are changed through the I
Note: The I
Table 6-2 Operation mode change
When set WP = “H”, only self-running mode is selected.
Operation mode is stored in R_MODE register. Table 6-3 shows the relationship between the Operation mode and
Table 6-3 R_MODE
6. Operation Mode
The AK2574 has 3 operating modes: Self-running, Adjustment and EEPROM mode.
6.1 Self-running Mode
Self-running mode is ready for normal operation after all adjustments are completed. In this mode, temperature
detection, EEPROM access and feeding current are automatically performed using the on-chip oscillator. The
AK2574 works in this mode after power-on.
6.2 Adjustment Mode
Adjustment mode is designed for training the LD characteristics. The AK2574 operates according to the register
6.3 EEPROM Mode
EEPROM mode is used for storing LD characteristics into EEPROM. Transition from EEPROM mode to
Adjustment mode is prohibition.
6.4 MODE Control
Table 6-1 Access limitation of each operation mode
6.5 Operation Mode Protection
6.6 Operation Mode Status
<MS0266-E-00>
settings set through the I
Operation mode
Self-running mode
(WP=”L”)
Adjustment mode
(WP=”L”)
EEPROM mode
(WP=”L”)
WP = “H”
Self-running mode only
Operation mode
Self-running mode
Adjustment mode
EEPROM mode
Device Address
1010100
1010100
1010100
2
C
TM
interface access is prohibited for 2ms after power-on or mode transfer to self-running mode.
2
C
TM
R/W
W
W
W
I/F.
(User Area Only)
R_MODE[3:0]
0000
0111
1110
Read
○
○
○
○
EEPROM Access
Address
11111111
11111111
11111111
Write
Data
10100000
10100111
10101110
×
×
○
×
2
C
TM
-27-
interface. Table 6-1 shows the access limitation of each
Read
○
○
○
×
Operation mode
Self-running mode
Adjustment mode
EEPROM mode
(except mode-change command)
(except mode-change command)
Register Access
Write
×
○
×
×
2003/12