IC-HTP Datasheet, PDF (31/51 Pages) IC-Haus GmbH – DUAL CW P-TYPE LASER DIODE DRIVER

iC-HTP
DUAL CW P-TYPE
LASER
DIODE
DRIVER
preliminary
Rev B1, Page 31/51
RACC2
Addr. 0x1A; bit 4
R/W 0
ADC2
Addr. 0x05/06; bit 9:0
R
0
Current range high for channel 2, Current sensor
0x000
ADC minimum value
resistor (Rsensex) set to 2kΩ
0x3FF
ADC maximum value
1
Current range low for channel 2, Current sensor
resistor (Rsensex) set to 16kΩ
Table 71: ADC channel 2
Table 69: Current range configuration channel 2
Since all of the above values are typical, a first cali-
bration measurement is recommended to calculate the
offset of each device.
When enabled, the A/D converter is continuously ac-
quiring the signal selected by ADCCx register. The
conversion time, is 140 µs. Changing the source re-
quires 500 µs settling time.
The voltage corresponding to the measured digital
value can be directly obtained through the following
formula:
V(LDAx, VB, VBLx)
=
11 ∗
VFS
1023
∗ ADCx
V (VDD)
=
8∗
VFS
1023
∗ ADCx
V(MDKx, PLRx)
=
VFS
1023
∗ ADCx
In order to do a measurement, register ADCx must be
read. The converter does not provide an end of conver-
sion (EOC) bit. Instead, ADCx register contains always
the value of the last conversion.
As the A/D converter is 10 bit long, the results are split
into two byte wide separated registers; ADCxh con-
tains channel x ADC MSBs values while ADCxl stores
the LSBs. A consecutive read action of both registers
(lower and upper part) should be carried out in order
to prevent an undesired change in the measured value
between two read actions.
ADC1
Addr. 0x03/04; bit 9:0
R
0x000
ADC minimum value
0x3FF
ADC maximum value
VFS is the full scale voltage of the A/D converter (cf.
Electrical Characteristics No. 706) typical 1.1 V. For
a more precise measurement, the A/D converter can
be calibrated by measuring a known VB voltage and
calculate the VFS.
If ADFNSx = 1 the sensing point is connected directly
to MDKx pin. Depending on the regulation voltage, it
is possible that V(MDKx) is higher than 1.1 V. When
MDKx pin is the source of the A/D converter, saturation
of the converter will occur. When monitoring pin MDKx
with the A/D converter, V(MDKx) must be lower than
1.1 V.
Table 70: ADC channel 1