32V Monolithic Li-Ion/Polymer Battery Chargers Deliver up to 2A in Compact 9mm2 Package

News Release ⎜ www.linear.com
32V Monolithic Li-Ion/Polymer Battery Chargers
Deliver up to 2A in Compact 9mm2 Package
MILPITAS, CA – June 17, 2009 – Linear Technology Corporation introduces the LT3650-4.1
and LT3650-4.2, compact, monolithic high-voltage battery chargers for single-cell
Li-Ion/Polymer batteries. The device’s switchmode architecture minimizes power dissipation
without compromising board space. The LT3650-4.1/4.2 operates from 4.75V to 32V and has a
40V absolute maximum rating for added system margin. User selectable timer or C/10
termination requires no external microcontroller and simplifies the design. Charge current is
programmable and dynamically adjustable up to 2A; the power device is integrated on chip to
save board space. The LT3650-4.1/4.2 does not require external high-precision resistors to set
the float voltage, further saving cost and space. Applications include industrial handheld
instruments, 12V to 24V automotive and heavy equipment, desktop cradle chargers and small
notebook or tablet computers. The LT3650-4.1 offers a 4.1V battery float voltage, allowing high
temperature safety margin, while the LT3650-4.2 features a 4.2V final charge voltage for
optimized battery run time.
The LT3650-4.1/4.2’s high operating frequency of 1MHz and current mode architecture
allow the use of small inductors and capacitors, minimizing noise and filtering needs. Final float
voltage accuracy is specified at ±0.5%, charge current accuracy is ±5% and C/10 detection
accuracy is ±2.5%. Once charging is terminated, the LT3650-4.1/4.2 automatically enters a low
current standby mode that reduces the input supply current to 85uA. In shutdown, the input bias
current is reduced to 15uA. The LT3650-4.1/4.2 maximizes battery life during all non-charging
periods, draining less than 1uA from the battery. For safety and autonomous charge control, the
LT3650-4.1/4.2 includes features such as automatic restart and preconditioning, a thermistor
input for temperature-qualified charging, programmable input current limit, bad battery detection
and binary coded status output pins.
32V Monolithic Li-Ion/Polymer Battery Chargers
Deliver up to 2A in Compact 9mm Package
page 2
The LT3650-4.1 and LT3650-4.2 are housed in a compact, low-profile (0.75mm) 12-pin
3mm x 3mm DFN package, and are offered in both E and I grade versions, both operating from
-40°C to +85°C. Pricing starts at $2.80 and $3.22, for the E & I grades respectively, in 1,000piece quantities. For more information, visit www.linear.com.
Photo Caption: 32V, 2A Monolithic 1-Cell Li Chargers
Summary of Features: LT3650-4.1 and LT3650-4.2
Wide Input Voltage Range: 4.75V to 32V (40V Absolute Maximum)
Programmable Charge Current up to 2A
User-Selectable Termination: C/10 or Programmable Termination Timer
Dynamic Charge Rate Programming/Soft-Start Pin
Battery Float Voltage: 4.1V (LT3650-4.1), 4.2V (LT3650-4.2)
Programmable Input Current Limit
1MHz Switching Frequency Enables Small External Components
±0.5% Charge Voltage Accuracy
±5% Charge Current Accuracy
±2.5% C/10 Detection Accuracy
NTC Resistor Temperature Monitor
Automatic Recharge
Automatic Preconditioning
Binary Coded Open-Collector Charge Status Pins
Bad Battery Detection with Auto-Reset
Compact, Low-Profile (0.75mm) 3mm x 3mm DFN-12 Package
About Linear Technology
Linear Technology Corporation, a manufacturer of high performance linear integrated circuits,
was founded in 1981, became a public company in 1986 and joined the S&P 500 index of major
public companies in 2000. Linear Technology products include high performance amplifiers,
comparators, voltage references, monolithic filters, linear regulators, DC-DC converters, battery
chargers, data converters, communications interface circuits, RF signal conditioning circuits,
uModule® products, and many other analog functions. Applications for Linear Technology’s
high performance circuits include telecommunications, cellular telephones, networking products
such as optical switches, notebook and desktop computers, computer peripherals,
video/multimedia, industrial instrumentation, security monitoring devices, high-end consumer
products such as digital cameras and MP3 players, complex medical devices, automotive
electronics, factory automation, process control, and military and space systems.
LT, LTC, LTM, uModule and
are registered trademarks of Linear Technology Corp. All other trademarks are the
property of their respective owners.
32V Monolithic Li-Ion/Polymer Battery Chargers
Deliver up to 2A in Compact 9mm Package
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Press Contacts:
North America
UK & Nordic
John Hamburger, Director Marketing
Tel 408-432-1900 ext 2419
Alan Timmins
Tel: +44-1252-629937
Doug Dickinson, Media Relations Manager
408-432-1900 ext 2233