EMC6D102-CZC-TR Standard Microsystems (SMSC), EMC6D102-CZC-TR Datasheet - Page 51

• Manufacturer Part Number: EMC6D102-CZC-TR
• Manufacturer: Standard Microsystems (SMSC)

Specifications of EMC6D102-CZC-TR

• Operating Current: 3mA
• Operating Temperature Classification: Commercial
• Package Type: SSOP
• Lead Free Status / Rohs Status: Compliant

Fan Control Device with Hardware Monitoring and Acoustic Noise Reduction Features
Datasheet
SMSC EMC6D102
7.2.6
Register
Address
30h
31h
32h
Note
Note
Note
Read/
Registers 30-32h: Current PWM Duty
Write
Note 7.8
The Current PWM Duty registers store the duty cycle that the chip is currently driving the PWM signals
at. At initial power-on, the duty cycle is 100% and thus, when read, this register will return FFh. After
the Ready/Lock/Start Register Start bit is set, this register and the PWM signals are updated based
on the algorithm described in the Auto Fan Control Operating Mode section and the Ramp Rate
Control logic, unless the associated fan is in manual mode – see below.
Note: When the device is configured for Manual Mode, the Ramp Rate Control logic should be
When read, the Current PWM Duty registers return the current PWM duty cycle for the respective
PWM signal.
These registers are read only – a write to these registers has no effect.
Note: If the current PWM duty cycle registers are written while the part is not in manual mode or
Manual Mode (Test Mode)
In manual mode, when the start bit is set to 1 and the lock bit is 0, the current duty cycle registers are
writeable to control the PWMs.
Note: When the lock bit is set to 1, the current duty cycle registers are Read-Only.
R
(See
R
(See
R
(See
/W
/W
/W
7.8)
7.8)
7.8)
disabled.
when the start bit is zero, the data will be stored in internal registers that will only be active
and observable when the start bit is set and the fan is configured for manual mode. While the
part is not in manual mode and the start bit is zero, the current PWM duty cycle registers will
read back FFh.
PWM1 Current Duty Cycle
PWM2 Current Duty Cycle
PWM3 Current Duty Cycle
These registers are only writable when the associated fan is in manual mode. These
registers become read only when the Lock bit is set. Any further attempts to write to these
registers shall have no effect.
Register Name
DATASHEET
(MSb)
Bit 7
7
7
7
51
Bit 6
6
6
6
Bit 5
5
5
5
Bit 4
4
4
4
Bit 3
3
3
3
Bit 2
2
2
2
Bit 1
1
1
1
Revision 0.4 (09-25-07)
(LSb)
Bit 0
0
0
0
Default
Value
N/A
N/A
N/A