IC-HTP Datasheet, PDF (36/51 Pages) IC-Haus GmbH – DUAL CW P-TYPE LASER DIODE DRIVER

iC-HTP
DUAL CW P-TYPE
LASER
DIODE
DRIVER
preliminary
Rev B1, Page 36/51
WATCHDOG TIMER
The internal 200 kHz oscillator is monitored with the
Watchdog Timer (WDT).
If the oscillator remains longer than the maximum time
of tWDT (cf. Electrical Characteristics No. E03) without
activity an oscillator error is triggered. An oscillator er-
ror sets OSCERR error bit to 1. The automatic offset
compensation of the laser control requires the oscillator.
The state of OSCERR is signaled at pin NCHK. The
signaling of OSCERR state can be masked with bit
MOSCERR. Setting MOSCERR to 1 masks the oscilla-
tor error and OSCERR will not be signaled at NCHK.
It is possible to simulate an error of the oscillator using
SOSCERR bit. If SOSCERR = 1, the oscillator error
is forced. When OSCERR is set to 1 the error will
be signaled through NCHK, depending on the state of
MOSCERR.
OSCERR
Addr. 0x00; bit 6
R
0
Oscillator functioning OK
1
Watchdog timeout set on oscillator failure.
Cleared on read
Table 73: Oscillator watchdog
MOSCERR
Addr. 0x1D; bit 0
R/W 0
0
Oscillator error (watchdog) will be signaled at NCHK
1
Oscillator error (watchdog) will not be signaled at
NCHK
Table 74: Oscillator watchdog error mask
SOSCERR
Addr. 0x1D; bit 7
R/W 0
0
No oscillator error simulated
1
Oscillator error simulated (watchdog timeout)
Table 75: Simulate oscillator error