ADP1147 Datasheet Text
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High Efficiency Step-Down Switching Regulator Controllers
ADP1147-3.3/ADP1147-5
Features
Greater Than 95% Efficiency Current Mode Switching Architecture Provides
Superior Load and Line Transient Response Wide Input Voltage Range 3.5 V- to 16 V User Defined Current Limit Short Circuit Protection Shutdown Pin Low Dropout Voltage Low Standby Current 160 A typ Low Cost Available in 8-Lead PDIP or 8-Lead SOIC
APPLICATIONS Portable puters Modems Cellular Telephones Portable Equipment GPS Systems Handheld Instruments
GENERAL DESCRIPTION The ADP1147 is part of a family of High Efficiency Step-Down Switching Regulators. These regulators offer superior load and line transient response, a user defined current limit and an automatic power savings mode. The automatic power savings mode is used to maintain efficiency at lower output currents. The ADP1147 incorporates a constant off-time, current mode switching architecture to drive an external P-channel MOSFET at frequencies up to 250 kHz. Constant off-time switching generates a constant ripple current in the external inductor. This results in a wider input voltage operating range of 3.5 V- to 16 V, and a less plex circuit design.
- 3.5 volt operation is for the ADP1147-3.3.
VIN (5.2V TO 12V)
+ 1F
+ CIN
100F
P-CHANNEL IRF7204
L- 50H D1 30BQ040
RSENSE-
- 0.05⍀
VOUT
5V/2A
+ COUT
390F
0V = NORMAL 1.5V = SHUTDOWN
VIN P-DRIVE
CC RC 3300pF 1k⍀
ADP1147
SHUTDOWN ITH SENSE(+)
CT SENSE(- )
CT
GND
470pF...