AK2572 Datasheet, PDF (1/50 Pages) Asahi Kasei Microsystems – APC for Burst Mode Applicable Direct Modulation Laser Diode

ASAHI KASEI
[AK2572]
AK2572
APC for Burst Mode Applicable Direct Modulation Laser Diode
FEATURES
■Temperature compensation programming function
(APC_FF) of Bias current (0~85mA) and Modulation
current (0~10mA/0~2.2V) responding to the detected
temperature by the On-chip temperature sensor.
■Stable feedback function in the digital scheme
(APC_FB).
■SFP support TXFAULT function and 1k bit ID field
(EEPROM User Area).
■LD Power leveling function by either Hardware pin
control or Register setting.
■Various alarm functions of Optical output decline
(OPTALM), Excessive LD current (CURRALM),
Exceptional temperature (TEMPALM) and Irregular
external signals (EXTALM1 and EXTALM2).
■Operation adjustment function via 2-wire Digital
interface after assembled into sub-system.
■On-chipOscillatorallows a Self-runningoperation.
■ Single 3.3 V [Typ.] power supply.
APPLICATIONS
For LD modules applied to Continuous and Burst mode
OUTLINES
The AK2572 enables to keep the optical power of the direct
modulation LD (Laser Diode) constant by the APC
(Automatic Power Control) circuit. It consists of a current
programming function (APC_FF) responding to the
temperature characteristics of each LD, and a Digital
feedback function (APC_FB) to adjust the LD current
based on the monitoring PD (Photo Diode) current.
The AK2572 is also applicable to the Burst mode
transmission. The device equips a Power leveling function
to switch a temperature compensation programming data
by either Hardware pin control or Register setting.
The On-chip EEPROM (Non-volatile memory) allows to
adjust and to keep the individual setting data for each LD
characteristics via 2-wire Digital interface after being
assembled into sub-system. As 1k bits User Area is
allocated in the EEPROM, which supports the ID field of
the SFP specification, a proper operation required for the
SFP module is realized by using the TXFAULT function.
ORDERING GUIDE
Product Number
AK2572
Package Type
QFN28 （5.2mm×5.2mm）
BLOCK DIAGRAM
AVDD AVSS DVDD DVSS VDDMD VDDBI VSSBI
TEMPMON
PDMON
Monitor PD
Cpd Rpd
BIAS
RB (12k)
TEMP
-SENS
R_TEMP
ADC
PDGAIN
PDIN
BURST
EXTALM2/MOD_CTRL
EXTALM1
BIAS_GEN
OSC
EEPROM
I-DAC1
APC V-DAC3
IOUT1
VOUT3
I-DAC2
IOUT2
ALM Detection
TEMPALM
CURRALM
OPTALM
EXTALM2
EXTALM1
BIAS
MON
(x0.012)
2-wire Digital I/F
SHUTDOW N
CONTROL
Imod
LDD LD
Vmod
Ibias
BIASMON
TXFAULT*
TXDIS
*:Open Drain
**:Internally Pulled-up ^{TEST1 TEST2 TEST3 TEST4 SCL SDA* W P**}
-1-
<MS0290-E-01>
2004/8