Rainbow Electronics LM93 - Manual (Page 64)

16.0 Registers
(Continued)
16.8.4 Register BFh PWM Ramp Control
Register
Address
Read/
Write
Register
Name
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Default
Value
BFh R/W
PWM Ramp
Control
PH_RAMP VRD_RAMP 00h
Bit Name R/W Description
3:0 VRD_RAMP R/W Sets the time delay between ramp steps for the
VRDx_HOT ramp up/ramp down PWM function.
7:4 PH_RAMP R/W 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
Time Delay between
Ramp Steps
0h 0 ms
1h 50 ms
2h 100 ms
3h 150 ms
4h 200 ms
5h 250 ms
6h 300 ms
7h 350 ms
8h 400 ms
9h 450 ms
Ah 500 ms
Bh 550 ms
Ch 600 ms
Dh 650 ms
Eh 700 ms
Fh 750 ms
16.8.5 Register C0h Fan Boost Hysteresis (Zones 1/2)
Register
Address
Read/
Write
Register
Name
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Default
Value
C0h R/W
Fan Boost
Hysteresis
(Zones 1/2)
H2 H1 44h
Bit Name R/W Description
3:0 H1 R/W Sets the fan boost hysteresis for zone 1
7:4 H2 R/W 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).
LM93
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