LTC2921/LTC2922 Series

1

29212fa

APPLICATIO S

FEATURES

DESCRIPTIO

TYPICAL APPLICATIO

2921/22 TA01

100

Ω

10

Ω

LTC2921

SENSE

100

Ω

100

Ω

4.7k

49.9k

49.9k

169k

243k

10

Ω

10

Ω

V1

V2

V3

V4

GATE

PG

GND

TIMER

Si1012R

CBRST

5V SUPPLY

3.3V SUPPLY

2.5V SUPPLY

Si2316DS

Si2316DS

Si2316DS

WSL1206

0.05

Ω

0.22

µF

5V

LOAD

3.3V

LOAD

2.5V

LOAD

RESET

0.47

µF

DC/DC

CONVERTER

DC/DC

CONVERTER

DC/DC

CONVERTER

100k

D1

D2

D3

S1

S2

S3

CIRCUIT BREAKER

RESET CONTROL

s

Desktop Computers

s

Plug-In Cards

s

Telecom Infrastructure

s

Supply Sequencing

s

Instruments

s

Tracks Multiple Supplies with MOSFET Switches

s

s

Guaranteed Threshold Accuracy:

±1% at 0.5V

s

Automatic Remote Sense Switching

s

Adjustable Supply Ramp Rate

s

Overvoltage Monitor

s

Adjustable Electronic Circuit Breaker

s

Adjustable Power-Good Delay

s

s

Available in 16-Pin Narrow SSOP (LTC2921 Series)

and 20-Pin TSSOP (LTC2922 Series)

Power Supply Tracker

with Input Monitors

The LTC

and force them to track on power-up in multiple supply

systems. Using external N-channel pass transistors, the

supplies can be ramped up at an adjustable rate. Auto-

matic remote sense switching allows the DC/DC convert-

ers to compensate for series voltage drops in the wiring.

An incorrect level on one or more of the supplies triggers

disconnect of all supplies. Tight 1% accuracy and glitch

immunity on the low 0.5V monitoring level ensure no false

error disconnects.

The LTC2921 and LTC2922 each feature an adjustable

short circuits. Capacitance at the TIMER pin programs the

delays in the monitoring sequence.

The LTC2921 includes three remote sense switches in a

16-pin narrow SSOP package, while the LTC2922 includes

five remote sense switches in a 20-pin TSSOP package.

3.3V, and 2.5V.

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

Three-Supply Tracker and Monitor (5V, 3.3V, 2.5V)

Load Voltage Ramp-Up and

Power-Good Activation

2921/22 TA01b

2.5V SUPPLY

2V/DIV

PG

2V/DIV

5V LOAD

3.3V LOAD

2.5V LOAD

5V SUPPLY AT 5V

3.3V SUPPLY AT 3.3V

100ms/DIV

OUTPUTS

2V/DIV