ncp5389 ON Semiconductor, ncp5389 Datasheet - Page 6

• Manufacturer Part Number: ncp5389
• Description: 2/3 Phase Buck Controller For Vr11 Pentium Iv Processor Applications
• Manufacturer: ON Semiconductor

PIN DESCRIPTIONS
17,19,21
18,20,22
24,25,26
Pin No.
1 - 8
10
11
12
13
14
15
16
23
27
28
29
30
31
32
33
9
VID0–VID7
DIFFOUT
VR_RDY
G1 – G3
Symbol
DRVON
THPAD/
ROSC2
COMP
DGND
ROSC
AGND
VDRP
CSxN
VCC
VS+
VFB
CSx
ILIM
VS-
EN
SS
Voltage ID DAC inputs.
Pull this pin high to enable controller. Pull this pin low to disable controller. Either an open-collector output
(with a pull-up resistor) or a logic gate (CMOS or totem-pole output) may be used to drive this pin. A Low to
High transition on this pin will initiate a soft start. If the Enable function is not required, this pin should be tied
directly to VREF.
A capacitor from this pin to ground programs the soft-start time.
Non-inverting input to the internal differential remote V
Inverting input to the internal differential remote V
Output of the differential remote sense amplifier.
Output of the error amplifier.
Error amplifier inverting input. Connect a resistor from this pin to DIFFOUT. The value of this resistor and the
amount of current from the droop resistor (R
load.
Current signal output for Adaptive Voltage Positioning (AVP). The voltage of this pin minus 1.3 V is
proportional to the output current. Connect a resistor from this pin to V
into the feedback resistor (R
Inverting input to current sense amplifier #x, x = 1, 2, 3
Non-inverting input to current sense amplifier #x, x = 1, 2, 3
Gate Driver enable output. This pin produces a logic HIGH to enable gate drivers and a logic LOW to disable
gate drivers and has an internal 70 kW to ground.
PWM control signal outputs to gate drivers.
Power supply return for the digital circuits. Connect to AGND.
Power for the internal control circuits.
Voltage Regulator Ready (PowerGood) output. Open drain type output with internal delays that will transition
High when V
and Low when V
mV until V
A resistance from this pin to ground programs the oscillator frequency. Also, this pin supplies a regulated
2.0 V which may be used with a voltage divider to the ILIM pin to set the over current shutdown threshold as
shown in the Applications Schematics.
Use for enhanced performance.
Over current shutdown threshold. To program the shutdown threshold, connect this pin to the R
resistor divider as shown in the Applications Schematics. To disable the over current feature connect this pin
directly to the R
generated by the R
Copper pad on the bottom of the IC for heatsinking. This pin should be connected to the ground plane under
the IC. Power supply return for the analog circuits that control output voltage.
CC
CORE
is removed.
OSC
CORE
is higher than 300 mV below DAC, Low when V
OSC
pin. To guarantee correct operation, this pin should only be connected to the voltage
is higher than DAC+185 mV. This output is latched Low if V
pin – do not connect this pin to any externally generated voltages.
FB
http://onsemi.com
) to produce an output voltage droop. Leave this pin open for no AVP.
NCP5389
6
DRP
Description
) will set the amount of output voltage droop (AVP) during
CORE
CORE
sense amplifier.
sense amplifier.
CORE
FB
is lower than 380 mV below DAC,
to set the amount of AVP current
CORE
exceeds DAC+185
OSC
pin via a