IC-HT_15 Datasheet, PDF (30/45 Pages) IC-Haus GmbH – DUAL CW LASER DIODE DRIVER

iC-HT
DUAL CW LASER DIODE DRIVER
preliminary
2.5V
VB
C3
2x10μF
C1
0.1μF
L1
1μH
L1
TPS63060
VIN
EN
VAUX
L2
VOUT
FB
PS/SYNC
GND
PG
PGND
3.3V
R1
100k
R3
1MEG
R2
6.7k
Rev B1, Page 30/45
48μA
C2
3x22μF
DUAL CW LASER DIODE DRIVER
CVB
1μF
CVDD
1μF
VB
VDD
VDD REGULATOR
- ^REF
+
VB UNDERVOLTAGE
VDD UNDERVOLTAGE
RAM
INTEGRITY
CHECK
0x10 0x30
0x1F 0x3F
RAM
REGISTERS
0x11 ILIM1(7:0)
0x13
0x14
REF1(9:8)
REF1(7:0)
ACC
8 Bit
D
A
10 Bit
D
A
OVC1
DCO
N
LDK1
+
ECIE1
CI
CI1
NCHK
EMC
NCS/A1
MOSI/A0
SCLK/SCL
CFGTIMO
Check
PODO
OVC
MEMERR
WATCHDOG
OVT
IO DRIVERS
WATCHDOG
TIMER
OSCILLATOR
0x03
0x04
ADC1(9:8)
ADC1(7:0)
0x10 ADCC1(2:0)
SPI/I2C
SLAVE
0x12 RMD1(7:0)
10 Bit
A
D
-
LDK1
VDD
VB
ADSNF1
EM C
R
8 Bit
DISP1
0
255
APC
PLR1
CIL1
AGND1
MDA1
MRL1
MISO/SDA
LASER CHANNEL 1
GND
INS/WKR
NSTBY
EC1
EC2
T.PAD
GND
TEMPERATURE
MONITOR 8 Bit
LASER
CONTROL
0x05
0x06
ADC2(9:8)
ADC2(7:0)
0x16 ILIM2(7:0)
0x18
0x19
REF2(9:8)
REF2(7:0)
0x17 RMD2(7:0)
0x02 TEMP(7:0)
LASER CHANNEL 2
LDK2
CI2
CIL2
AGND2
MDA2
MRL2
Figure 19: Extension of working voltage range
In the figure 19 both the laser and the iC-HT are sup-
plied by output voltage Vout from DC/DC converter.
The register RDCO is set to 23, which forces 48 µA
to be output to the voltage divider. A system voltage of
3.3 V is obtained at Vout.
Efficiency enhancement
If iC-HT and the laser diode are supplied with the same
power supply, the efficiency of the driver can be poor,
depending on the supplied voltage, the saturation volt-
age and the laser diodes forward voltage. Power dis-
sipation of the driver can be reduced if LDAx is fed
through the DC/DC converter configured to deliver a
lower voltage than the power supply as shown in fig-
ure 20.