High Efficiency Synchronous
a
Step-Down Switching Regulators
ADP1148, ADP1148-3.3, ADP1148-5
FEATURES
FUNCTIONAL BLOCK DIAGRAM
Operation From 3.5 V to 18 V Input Voltage
Ultra High Efficiency > 95%
Low Shutdown Current
Current Mode Operation for Excellent Line & Load
Transient Response
ADJUSTABLE
VERSION
SIGNAL
GND
PWR
GND
12
V
V
IN PDRIVE NDRIVE
SENSE(+)
8
FB
9
SENSE(–)
7
3
1
11
14
ADP1148
High Efficiency Maintained Over Wide Current Range
Logic Controlled Micropower Shutdown
Short Circuit Protection
NON-OVERLAP
DRIVE
V
B
2
R
SLEEP
Very Low Dropout Operation
Q
S
1
Synchronous FET Switching for High Efficiency
Adaptive Nonoverlap Gate Drives
R
S
Q
C
S
V
TH1
APPLICATIONS
13kΩ
10mV to
150mV
V
TH2
T
G
100kΩ
Notebook and Palmtop Computers
Portable Instruments
Battery Operated Digital Devices
Industrial Power Distribution
Avionics Systems
1.25V
V
IN
SENSE(–)
OFF-TIME
CONTROL
REFERENCE
V
FB
5
4
6
10
SHUTDOWN
I
INT V
CC
C
TH
T
Telecom Power Supplies
GPS Systems
Cellular Telephones
The constant off-time architecture maintains constant ripple
current in the inductor, easing the design of wide input range
converters. Current-mode operation provides excellent line and
load transient response. The operating current level is user
programmable via an external current sense resistor.
GENERAL DESCRIPTION
The ADP1148 is part of a family of synchronous step-down
switching regulator controllers featuring automatic sleep mode
to maintain high efficiencies at low output currents. These
devices drive external complementary power MOSFETs at
switching frequencies up to 250 kHz using a constant off-time
current-mode architecture.
The ADP1148 incorporates automatic Power Saving Sleep
Mode operation when load currents drop below the level
required for continuous operation. In sleep mode, standby
power is reduced to only about 2 mW at VIN = 10 V. In
shutdown, both MOSFETs are turned off.
TYPICAL APPLICATIONS
V
(5.2V TO 18V)
IN
+
+
C
100
95
90
85
80
1µF
IN
100µF
V
10nF
IN
V
V
= 6V
IN
INT V
CC
P-CH
IRF7204
P-DRIVE
= 10V
IN
ADP1148
R
**
L*
OV = NORMAL
SENSE
62µH
0.05Ω
>1.5V = SHUTDOWN
SHUTDOWN
V
OUT
5V/2A
I
SENSE(+)
TH
1000pF
R
C
C
SENSE(–)
N-DRIVE
T
1kΩ
C
+
OUT
N-CH
IRF7403
390µF
C
T
75
70
470pF
C
C
FIGURE 1 CIRCUIT
0.02
C1
10BQ040
S-GND P-GND
3300pF
2
0.2
LOAD CURRENT – A
*COILTRONICS CTX-68-4
**KRL SL-1-C1-0R050L
Figure 1. High Efficiency Step-Down Converter
REV. 0
Figure 2. ADP1148-5 Typical Efficiency
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 617/329-4700
Fax: 617/326-8703
World Wide Web Site: http://www.analog.com
© Analog Devices, Inc., 1996
5秒后页面跳转
电子元器件中的网络滤波器、EMI滤波器与EMC滤波器：分类关系与功能详解
NTC热敏电阻与PTC热敏电阻的应用原理及应用范围
GTO与普通晶闸管相比为什么可以自关断？为什么普通晶闸管不能呢？从GTO原理、应用范围带你了解原因及推荐型号
LF353数据手册解读：特性、应用、封装、引脚说明、电气参数及替换型号推荐
微信公众号
抖音公众号
浙公网安备 33010502006866号 浙ICP备10014259号-119
营业执照ICP证
数据手册
如果您发现信息不准确，
