NCP81241
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Table 6. STATE TRUTH TABLE
STATE VR_RDY Pin Error AMP Comp Pin OVP & UVP Method of Reset
POR
0<VCC<UVLO
N/A N/A N/A
Disabled
EN < threshold
UVLO >threshold
Low Low Disabled
Start up Delay & Calibration
EN> threshold
UVLO>threshold
Low Low Disabled
Soft Start
EN > threshold
UVLO >threshold
Low Operational Active /
No latch
Normal Operation
EN > threshold
UVLO >threshold
High Operational Active /
Latching
N/A
Over Voltage Low N/A DAC+OVP Limit
Over Current Low Operational Last DAC Code
VID Code = 00h Low: if Reg34h:bit0=0;
High:if Reg34h:bit0=1;
Clamped at 0.9 V Disabled
General
The NCP81241 is a single phase PWM controller with
integrated driver, designed to meet the Intel VR12.1
specifications with a serial SVID control interface. The
NCP81241 implements PS0, PS1, PS2, PS3 and PS4 power
saving states. It is designed to work in notebook and desktop
applications.
Power Status Output Operating Mode
PS0 Single−phase RPM CCM mode
PS1 Single−phase RPM CCM mode – low pow-
er mode
PS2 Single−phase RPM DCM mode –very low
power mode
PS3 Single−phase RPM DCM mode– ultra low
power mode
PS4 Vout to 0 V, no phase state
The NCP81241 has one internal Driver: DRV1. Internally,
there is a single PWM signal: PWM1. DRV1 is driven by
PWM1.
SVID Address and Boot Voltage Programming
The NCP81241 has a Vboot voltage register that can be
externally programmed. The boot voltage for the NCP81241
is set using VBOOT/ADDR pin on power up. A 10 uA
current is sourced from the VBOOT/ADDR pin and the
resulting voltage is measured. This is compared with the
thresholds in the table below and the corresponding values
for Vboot and SVID address are configured. These values
are programmed on power up and cannot be changed after
the initial power up sequence is complete.
Table 7. SVID ADDRESS AND BOOT VOLTAGE TABLE
VBOOT/ADDR
Resistor (Ohm)
SVID Address Vboot (V)
0 0x0 1.0
14.0 k 0x1 1.0
22.1 k 0x2 1.0
30.1 k 0x3 1.0
39.2 k 0x4 1.0
48.7 k 0x5 1.0
57.6 k 0x6 1.0
68.1 k 0x7 1.0
78.7 k 0x8 1.1
88.7 k 0x0 1.1
100 k 0x1 1.1
113 k 0x2 1.1
124 k 0x3 1.1
137 k 0x4 1.1
150 k 0x5 1.1
165 k 0x6 1.1
182 k 0x7 1.1
196 k 0x8 1.1
