Rainbow Electronics LM93 - Manual (Page 66)

16.0 Registers
(Continued)
16.8.8 Register C3h Zones 1/2 MinPWM and Hysteresis
Register
Address
Read/
Write
Register
Name
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Default
Value
C3h R/W
Zones 1/2
MinPWM and
Hysteresis
MinPWM FC_TH N/D
Bit Name R/W Description
3:0 FC_TH R/W This field sets the amount of hysteresis (in degrees
C) that is used by the auto-fan control for zones 1
and 2. This should be set greater than 0 to avoid
unwanted oscillation between two steps in the look-up
table.
7:4 MinPWM R/W This field determines the duty cycle that the auto-fan
control requests for zones 1 and 2 if the temperature
for the given zone falls below the programmed base
temperature for that zone. This field accepts 16
possible values that are mapped to duty cycles
according the table in the Auto-Fan Control section.
16.8.9 Register C4h Zones 3/4 MinPWM and Hysteresis
Register
Address
Read/
Write
Register
Name
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Default
Value
C4h R/W
Zones 3/4
MinPWM and
Hysteresis
MinPWM FC_TH N/D
Bit Name R/W Description
3:0 FC_TH R/W This field sets the amount of hysteresis (in degrees
C) that is used by the auto-fan control for zones 3
and 4. This should be set greater than 0 to avoid
unwanted oscillation between two steps in the look-up
table.
7:4 MinPWM R/W This field determines the duty cycle that the auto-fan
control requests for zones 3 and 4 if the temperature
for the given zone falls below the programmed base
temperature for that zone. This field accepts 16
possible values that are mapped to duty cycles
according the table in the Auto-Fan Control section.
LM93
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