LM93
16.0 Registers
Register
Address
BFh
Read/
Write
R/W
(Continued)
16.8.4 Register BFh PWM Ramp Control
Register
Name
PWM Ramp
Control
Bit
3:0
7:4
Name
VRD_RAMP
PH_RAMP
R/W
R/W
R/W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Default
Value
00h
PH_RAMP
VRD_RAMP
Description
Sets the time delay between ramp steps for the
VRDx_HOT ramp up/ramp down PWM function.
Sets the time delay between ramp steps for the
Px_PROCHOT ramp up/ramp down PWM function.
If the time delay between steps is set to 0 ms, the PWM duty cycle goes immediately to 100% instead of ramping up gradually.
VRD_RAMP
or PH_RAMP
0h
1h
2h
3h
4h
5h
6h
7h
8h
9h
Ah
Bh
Ch
Dh
Eh
Fh
16.8.5 Register C0h
Register
Address
C0h
Read/
Write
R/W
Fan Boost Hysteresis (Zones 1/2)
Register
Name
Fan Boost
Hysteresis
(Zones 1/2)
Bit
3:0
7:4
Name
H1
H2
R/W
R/W
R/W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Default
Value
44h
Time Delay between
Ramp Steps
0 ms
50 ms
100 ms
150 ms
200 ms
250 ms
300 ms
350 ms
400 ms
450 ms
500 ms
550 ms
600 ms
650 ms
700 ms
750 ms
H2
H1
Description
Sets the fan boost hysteresis for zone 1
Sets the fan boost hysteresis for zone 2
If the temperature zone is above fan boost temperature and then drops below the fan boost temperature, the following occurs:
the PWM output remains at 100% until the temperature goes a certain amount below the fan boost temperature. These hysteresis
registers control this amount and can be set anywhere from 0˚C to 15˚C (unsigned).
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