MAX1551EZK Datasheet, PDF (1/8 Pages) Maxim Integrated Products – SOT23 Dual-Input USB/AC Adapter 1-Cell Li Battery Chargers

AVAILABLE
MAX1551/MAX1555
SOT23 Dual-Input USB/AC Adapter 1-Cell Li+
Battery Chargers
General Description
The MAX1551/MAX1555 charge a single-cell lithium-ion
(Li+) battery from both USB and AC adapter sources.
They operate with no external FETs or diodes, and
accept operating input voltages up to 7V.
On-chip thermal limiting simplifies PC board layout and
allows optimum charging rate without the thermal limits
imposed by worst-case battery and input voltage. When
the MAX1551/MAX1555 thermal limits are reached, the
chargers do not shut down, but progressively reduce
charging current.
The MAX1551 includes a POK output to indicate when
input power is present. If either charging source is
active, POK goes low. The MAX1555 instead features a
CHG output to indicate charging status.
With USB connected, but without DC power, charge cur-
rent is set to 100mA (max). This allows charging from
both powered and unpowered USB hubs with no port
communication required. When DC power is connected,
charging current is set at 280mA (typ). No input-blocking
diodes are required to prevent battery drain.
The MAX1551/MAX1555 are available in 5-pin thin SOT23
packages and operate over a -40°C to +85°C range.
Applications
PDAs
Wireless Appliances
Cell Phones _{Functional Diagrams}
Digital Cameras
Features
♦ Charge from USB or AC Adapter
♦ Automatic Switchover when AC Adapter is
Plugged In
♦ On-Chip Thermal Limiting Simplifies Board
Design
♦ Charge Status Indicator
♦ 5-Pin Thin SOT23 Package
PART
MAX1551EZK-T
MAX1555EZK-T
Ordering Information
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
5 Thin SOT23-5
5 Thin SOT23-5
PART
MAX1551EZK
MAX1555EZK
Selector Guide
TOP MARK
ADRT
ADRU
FEATURES
POK Output
CHG Output
Pin Configuration
Typical Operating Circuit
TOP VIEW
USB 1
5 BAT
MAX1551
GND 2 _(MAX1555)
POK 3
(CHG)
4 DC
THIN SOT23
Pin Configurations appear at end of data sheet.
Functional Diagrams continued at end of data sheet.
UCSP is a trademark of Maxim Integrated Products, Inc.
AC ADAPTER
DC
BAT
3.7V TO 7V
USB
3.7V TO 6V
CHARGE
USB
CONTROL
MAX1551
(MAX1555)
LOGIC
POK
CONTROL (CHG)
GND
TO SYSTEM
LOAD
Li+
TO LOGIC RAIL
For pricing, delivery, and ordering information, please contact Maxim Direct
at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.
19-2902; Rev 0; 7/03