ncp5372 ON Semiconductor, ncp5372 Datasheet - Page 15

• Manufacturer Part Number: ncp5372
• Description: High Efficiency Two-phase Step-down Power Controller For Imvp-6.5 Mobile Cpu Core Power Supplies
• Manufacturer: ON Semiconductor

VID Inputs
Once the output almost achieves Vboot, a 75uS (+/- 30uS) timer will be initialized and the VID code will not be
valid until the CLK_ENABLE# pulled low when the timer expires. After the timer expires, the new DAC voltage
will be applied to the controller to follow but the change will NOT be limited by the soft start ramp any more.
However, when the reference is switched from 0V to a DAC voltage, the soft start ramp control will be applied in
order to limit the transient input current consumption from VBAT.
VID SELECTOR
The VID at startup will be externally programmed by a resistor divider from Vref. When Vcc_core almost reaches Vboot, the
external VID code is selected and applied to controller after the timing of Tcpu+Tboot. See Soft Start Timing shown in figure
3.
OUTPUT TOLERANCE ANALYSIS
The DAC Tolerance minimum requirement was back calculated from the overall system regulation
requirements. The DAC regulation requirement is measured across VS+ and VS- pins.
Requirements
-2.0mOhm Load Line
1.5V – 0.7625V
0.75V – 0.5V
0.4875 – 0.3V
Note: CODE 1111111 is a special OFF code condition. After receiving OFF code, the controller initiates
power off sequencing. IMVP_PWRGD is de-asserted within T
initialization.
Table 1. VID vs. Output Voltage Table
VID6
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
VID5
Rev0.3
+/- 1.5% Total System Tolerance (Excludes Ripple)
+/- 11.5mV Total System Tolerance (Excludes Ripple)
+/- 25mV Total System Tolerance (Excludes Ripple)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Confidential and Proprietary – Not for Public Release
VID4
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
VID3
(Only monotonicity can be guaranteed to decrement when Vout is lower than 0.25V)
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
ON Semiconductor CONFIDENTIAL
VID2
Mar 19, 2008 - Page 13
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
VID1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
VID0
PWRDOWN1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
52A Maximum Load
52A Maximum Load
3A Maximum Load
Vout
1.5000
1.4875
1.4750
1.4625
1.4500
1.4375
1.4250
1.4125
1.4000
1.3875
1.3750
1.3625
1.3500
1.3375
1.3250
1.3125
1.3000
1.2875
1.2750
1.2625
1.2500
after power off sequencing