© Semiconductor Components Industries, LLC, 2017
June, 2017 − Rev. 14
1 Publication Order Number:
NCP81274/D
NCP81274
8/7/6/5/4/3/2/1 Phase Buck
Controller with PWM_VID
and I
2
C Interface
The NCP81274 is a multiphase synchronous controller optimized
for new generation computing and graphics processors. The device is
capable of driving up to 8 phases and incorporates differential voltage
and phase current sensing, adaptive voltage positioning and
PWM_VID interface to provide and accurately regulated power for
computer or graphic controllers. The integrated power saving
interface (PSI) allows for the processors to set the controller in one of
three modes, i.e. all phases on, dynamic phases shedding or fixed low
phase count mode, to obtain high efficiency in light-load conditions.
The dual edge PWM multiphase architecture ensures fast transient
response and good dynamic current balance.
Features
• Compliant with NVIDIA
®
OVR4+ Specifications
• Supports Up to 8 Phases
• 4.5 V to 20 V Supply Voltage Range
• 250 kHz to 1.2 MHz Switching Frequency (8 Phase)
• Power Good Output
• Under Voltage Protection (UVP)
• Over Voltage Protection (OVP)
• Over Current Protection (OCP)
• Per Phase Over Current Protection
• Startup into Pre-Charged Loads while Avoiding False OVP
• Configurable Adaptive Voltage Positioning (AVP)
• High Performance Operational Error Amplifier
• True Differential Current Balancing Sense Amplifiers for Each
Phase
• Phase-to-Phase Dynamic Current Balancing
• Current Mode Dual Edge Modulation for Fast Initial Response to
Transient Loading
• Power Saving Interface (PSI)
• Automatic Phase Shedding with User Settable Thresholds
• PWM_VID and I
2
C Control Interface
• Compact 40 Pin QFN Package (5 × 5 mm Body, 0.4 mm Pitch)
• This Device is Pb-Free and is RoHS Compliant
Typical Applications
• GPU and CPU Power
• Graphic Cards
• Desktop and Notebook Applications
MARKING DIAGRAM
QFN40
CASE 485CR
www.onsemi.com
401
NCP
81274
AWLYYWWG
G
1
NCP81274 = Specific Device Code
A = Assembly Location
WL = Wafer Lot
YY = Year
WW = Work Week
G = Pb-Free Package
(Note: Microdot may be in either location)
ON
PIN CONNECTIONS
31
32
33
34
35
36
37
38
39
40
20
19
18
17
16
15
14
13
12
11
1
2
3
4
5
6
7
8
9
10
30
29
28
27
26
25
24
23
22
21
VSP
VSN
VCC
SDA
SCL
EN
PSI
PGOOD
VID_BUFF
PWM_VID
CSP1
CSP2
CSP3
CSP4
CSP5
CSP6
CSP7
CSP8
DRON
PWM1/
PHTH4
REFIN
VREF
VRMP
PWM8/SS
PWM7/OCP
PWM6/LPC1
PWM5/LPC2
PWM4/PHTH1
PWM3/PHTH2
PWM2/PHTH3
COMP
FB
DIFF
FSW
LLTH/I2C_ADD
IOUT
ILIM
CSCOMP
CSSUM
CSREF
NCP81274
(TOP VIEW)
Tab: GROUND
Device Package Shipping
†
ORDERING INFORMATION
NCP81274MNTXG QFN40
(Pb-Free)
5000/Tape & Ree
†For information on tape and reel specifications,
including part orientation and tape sizes, please
refer to our Tape and Reel Packaging Specification
Brochure, BRD8011/D
.
