NCP3121 Datasheet, PDF (1/41 Pages) ON Semiconductor – Dual 3.0 A, Step-Down DC/DC Switching Regulator

NCP3121
Dual 3.0 A, Step-Down
DC/DC Switching Regulator
The NCP3121 is a dual buck converter designed for low voltage
applications requiring high efficiency. This device is capable of
producing an output voltage as low as 0.8 V. The NCP3121 provides
dual 3.0 A switching regulators with an adjustable 200 kHz − 750 kHz
switching frequency. The switching frequency is set by an external
resistor. The NCP3121 also incorporates an auto−tracking and
sequencing feature. Protection features include cycle−by−cycle
current limit and undervoltage lockout (UVLO). The NCP3121 comes
in a 32−pin QFN package.
Features
• Input Voltage Range from 4.5 V to 13.2 V
• 12 V_in to 5.0 V_out = 85% Efficiency Min @ 3.0 A
• 200−750 kHz Operation
• Stable with Low ESR Ceramic Output Capacitor
• 0.8 ±1.5% FB Reference Voltage
• External Soft−Start
• Out of Phase Operation of OUT1 & OUT2
• Auto−Tracking and Sequencing
• Enable/Disable Capability
• Hiccup Overload Protection
• Low Shutdown Power (I_q < 100 mA)
http://onsemi.com
1 32
QFN32
CASE 488AM
MARKING DIAGRAM
1
NCP3121
AWLYYWWG
G
NCP3121 = 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)
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 40 of this data sheet.
Typical Applications
• Set−Top Boxes, Portable Applications, Networking and
Telecommunications
• DSP/mP/FPGA Core
VIN
RVIN
R_TRACK
PG1
PG2
Enable
EN1
Disable
Enable
Disable
EN2
R14
R24
C3
GND
PG1
PG2
EN1
SEQ1
EN2
SEQ2
TRACK1,2
NCP3121
RT
C22
R23
SW1
VIN
SW2
C12
R13
L11
D11
GND
C1
GND
L21
D21
GND
C2
GND
OUT1
R11
C11
R12
GND
GND
OUT2
R21
C21
GND
R22
GND
GND
C23 _GND
C13
GND
GND
Figure 1. Typical Application Circuit
© Semiconductor Components Industries, LLC, 2008
1
October, 2008 − Rev. 1
Publication Order Number:
NCP3121/D