19-3336; Rev 2; 6/10
16µA I , 1.2A PWM
Q
Step-Down DC-DC Converters
6/MAX157
General Description
Features
The MAX1556/MAX1556A/MAX1557 are low-operating-
current (16µA), fixed-frequency step-down regulators.
High efficiency, low-quiescent operating current, low
dropout, and minimal (27µA) quiescent current in
dropout make these converters ideal for powering
portable devices from 1-cell Li-ion or 3-cell alkaline/NiMH
batteries. The MAX1556 delivers up to 1.2A; has pin-
selectable 1.8V, 2.5V, and 3.3V outputs; and is also
adjustable. The MAX1557 delivers up to 600mA; has pin-
selectable 1V, 1.3V, and 1.5V outputs; and is also
adjustable.
o Up to 97% Efficiency
o 95% Efficiency at 1mA Load Current
o Low 16µA Quiescent Current
o 1MHz PWM Switching
o Tiny 3.3µH Inductor
o Selectable 3.3V, 2.5V, 1.8V, 1.5V, 1.3V, 1.2V, 1.0V,
and Adjustable Output
o 1.2A Guaranteed Output Current
(MAX1556/MAX1556A)
The MAX1556/MAX1556A/MAX1557 contain a low-on-
resistance internal MOSFET switch and synchronous
rectifier to maximize efficiency and dropout perfor-
mance while minimizing external component count. A
proprietary topology offers the benefits of a high fixed-
frequency operation while still providing excellent effi-
ciency at both light and full loads. A 1MHz PWM
switching frequency keeps components small. Both
devices also feature an adjustable soft-start to minimize
battery transient loading.
o Voltage Positioning Optimizes Load-Transient
Response
o Low 27µA Quiescent Current in Dropout
o Low 0.1µA Shutdown Current
o No External Schottky Diode Required
o Analog Soft-Start with Zero Overshoot Current
o Small, 10-Pin, 3mm x 3mm TDFN Package
The MAX1556/MAX1556A/MAX1557 are available in a
tiny 10-pin TDFN (3mm x 3mm) package.
Ordering Information
TOP
MARK
Applications
PART
TEMP RANGE PIN-PACKAGE
PDAs and Palmtop Computers
Cell Phones and Smart Phones
Digital Cameras and Camcorders
Portable MP3 and DVD Players
Hand-Held Instruments
MAX1556ETB+
-40°C to +85°C 10 TDFN-EP*
ACQ
AUJ
ACR
MAX1556AETB+ -40°C to +85°C 10 TDFN-EP*
MAX1557ETB+ -40°C to +85°C 10 TDFN-EP*
*EP = Exposed paddle.
+Denotes a lead(Pb)-free/RoHS-compliant package.
Typical Operating Circuit
Pin Configuration
OUTPUT
0.75V TO V
TOP VIEW
INPUT
2.6V TO 5.5V
IN
INP
LX
MAX1556
MAX1556A
MAX1557
1
2
3
4
5
IN
10 D1
GND
SS
INP
LX
9
8
7
6
IN
PGND
MAX1556
MAX1556A
MAX1557
D1
D2
VOLTAGE
SELECT
PGND
D2
OUT
SHDN
OUT
SS
ON
OFF
SHDN
GND
TDFN
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
5秒后页面跳转
MAX487芯片引脚图及功能、应用领域详解
IR2110驱动芯片引脚图及功能、电路图详解
74LS74是什么芯片 74LS74引脚图及功能表
CD4511芯片引脚图及功能、电路图解析
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，
