1

LTC4412HV

sn4412hv 4412hvfs

APPLICATIO S

FEATURES

DESCRIPTIO

TYPICAL APPLICATIO

36V, Low Loss PowerPath

TM

Controller in ThinSOT

s

Very Low Loss Replacement for Power Supply

OR’ing Diodes

s

3V to 36V AC/DC Adapter Voltage Range

s

–40

°C to 125°C Operating Temperature Range

s

Minimal External Components

s

Automatic Switching Between DC Sources

s

Simplifies Load Sharing with Multiple Batteries

s

Low Quiescent Current: 11

µA

s

2.5V to 36V Battery Voltage Range

s

Reverse Battery Protection

s

Drives Almost Any Size MOSFET for Wide Range of

Current Requirements

s

MOSFET Gate Protection Clamp

s

Manual Control Input

s

Low Profile (1mm) SOT-23 (ThinSOT

s

Industrial and Automotive Applications

s

Notebook and Handheld Computers

s

USB-Powered Peripherals

s

Uninterruptable Power Supplies

s

Logic Controlled Power Switch

The LTC

to create a near ideal diode function for power switchover

or load sharing. This permits highly efficient OR’ing of mul-

tiple power sources for extended battery life and low self-

heating. When conducting, the voltage drop across the

MOSFET is typically 20mV. For applications with a wall

adapter or other auxiliary power source, the load is auto-

matically disconnected from the battery when the auxiliary

source is connected. Two or more LTC4412HVs may be in-

terconnected to allow load sharing between multiple bat-

teries or charging of multiple batteries from a single charger.

The LTC4412HV is an extended supply and temperature

range version of the LTC4412.

The wide supply operating range supports operation from

one to eight Li-Ion cells in series. The low quiescent

current (11

µA typical) is independent of the load current.

The gate driver includes an internal voltage clamp for

MOSFET protection.

The STAT pin can be used to enable an auxiliary P-channel

MOSFET power switch when an auxiliary supply is

detected. This pin may also be used to indicate to a micro-

controller that an auxiliary supply is connected. The con-

trol (CTL) input enables the user to force the primary

MOSFET off and the STAT pin low.

The LTC4412HV is available in a low profile (1mm) SOT-23

package.

, LTC and LT are registered trademarks of Linear Technology Corporation.

PowerPath and ThinSOT are trademarks of Linear Technology Corporation.

GND

CTL

SENSE

GATE

STAT

1

2

3

6

5

4

LTC4412HV

TO LOAD

STATUS OUTPUT

LOW WHEN WALL

ADAPTER PRESENT

470k

4412HV F01

1N5819

FDN306P

BATTERY

CELL(S)

WALL

ADAPTER

INPUT

Figure 1. Automatic Switchover of Load Between a Battery and a Wall Adapter

FORWARD VOLTAGE (V)

0.02

0

1

CONSTANT

4412HV F01b

0.5

CONSTANT

VOLTAGE

SCHOTTKY

DIODE

LTC4412HV

LTC4412HV vs Schottky Diode Forward Voltage Drop