lm96163cisdx-1 National Semiconductor Corporation, lm96163cisdx-1 Datasheet - Page 21

• Manufacturer Part Number: lm96163cisdx-1
• Description: Remote Diode Digital Temperature Sensor With Integrated Fan Control And Trutherm Bjt Transistor Beta Compensation Technology
• Manufacturer: National Semiconductor Corporation

Address
4B
4C
4D
4E
4F
Hex
HEX
HEX
HEX
HEX
HEX
4C
4D
4B
4E
4F
LOOKUP TABLE TEMPERATURE OFFSET
LOOKUP TABLE HYSTERESIS
FAN SPIN-UP CONFIGURATION REGISTER
PWM VALUE REGISTER
FAN PWM FREQUENCY REGISTER
reg 4A
5 = 1.)
Read/
(Write
only if
Write
Read
R/W
R/W
R/W
R/W
bit
R
R
R
R
Bits
7:6
4:3
2:0
7:6
5:0
7:5
4:0
7:6
5:0
7:5
4:0
5
Value
POR
0x00
0x17
0x00
0x04
111
000
000
11
00
00
0
1
SPNTIM2:SPNTIM
PWVAL5:PWVAL0
LOOKH4:LOOKH0
SPNDTY1:SPNDT
HPWVAL7:HPWV
PWMF4:PWMF0
[Reserved]
[Reserved]
[Reserved]
[Reserved]
TO5:TO0
SPINUP
Name
AL6
Y0
0
These bits are unused and always read as 0
Fast Tachometer Spin-up
If 0, the fan spin-up uses the duty cycle and spin-up time, bits 0–4.
If 1, the LM96163 sets the PWM output to 100% until the spin-up times out (per
bits 0–2) or the minimum desired RPM has been reached (per the Tachometer
Setpoint setting) using the tachometer input, whichever happens first. This bit
overrides the PWM Spin-Up Duty Cycle register (bits 4:3)—PWM output is
always 100%. Register x03, bit 2 = 1 for Tachometer mode.
If PWM Spin-Up Time (bits 2:0) = 000, the Spin-Up cycle is bypassed, regardless
of the state of this bit.
PWM Spin-Up Duty Cycle
00: Spin-Up cycle bypassed (no Spin-Up), unless Fast Tachometer Terminated
Spin-Up (bit 5) is set.
01: 50%
10: 75%–81% Depends on PWM Frequency. See Applications Notes.
11: 100%
PWM Spin-Up Time Interval
000: Spin-Up cycle bypassed (No Spin-Up)
001: 0.05 seconds
010: 0.1 s
011: 0.2 s
100: 0.4 s
101: 0.8 s
110: 1.6 s
111: 3.2 s
PWM High Resolution and Low Resolution Values
If PWM Program (register 4A, bit 5) = 0 this register is read only, this register
reflects the LM96163’s current PWM value from the Lookup Table.
If PWM Program (register 4A, bit 5) = 1, this register is read/write and the desired
PWM value is written directly to this register, instead of from the Lookup Table,
for direct fan speed control.
This register will read 0 during the Spin-Up cycle.
See Application Notes section at the end of this datasheet for more information
regarding the PWM Value and Duty Cycle in %.
These bits are unused and always read as 0
PWM Output Frequency
The PWM Frequency = PWM_Clock / 2n, where PWM Master Clock = 360 kHz
or 1.4 kHz (per the PWM Master Clock Select bit in Register 4A), and n = value
of the register. Note: n = 0 is mapped to n = 1. See the Application Note at the
end of this datasheet.
These bits are unused and always read as 0.
The temperature offset applied to the temperature values of the lookup table.
This offset allows the lookup table temperature settings to be extended above
127°C. The value, which is always positive, has an unsigned format with 1°C
resolution. The maximum offset that can be programmed is +63°C.
These bits are unused and always read as 0
Lookup Table Hysteresis
The amount of hysteresis applied to the Lookup Table. (1 LSb = 1°C, max value
31°C, default value 10°C).
21
Description
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