LTC2934

1

2934f

TYPICAL APPLICATION

FEATURES

APPLICATIONS

DESCRIPTION

Ultra-Low Power

Adjustable Supervisor with

Power-Fail Output

system initialization, power-fail warning and reset gen-

eration functions. Low quiescent current (500nA typical)

makes the LTC2934 an ideal choice for battery-operated

applications.

Precision power-fail and reset voltages can be configured

independently. Early warning of an impending low volt-

age condition is provided at the power-fail output (PFO)

when the PFI input falls below 0.4V. Supervisory circuits

monitor the ADJ input and pull RST low when ADJ falls

below 0.4V. When ADJ is rising from an under-threshold

condition, an internal reset timer is started after exceeding

the ADJ threshold by 5%. The reset timeout delays the

return of the RST output to a high state. A pushbutton

switch connected to the MR input is typically used to

force a manual reset. Outputs RST and PFO are available

with open-drain (LTC2934-1) or active pull-up circuits

(LTC2934-2). Operating temperature range is from –40ºC

to 85ºC.

Configurable Low Power Voltage Supervisor

× 2mm DFN and TSOT-23

(ThinSOT™) Packages

, LT, LTC, LTM are registered trademarks of Linear Technology Corporation. ThinSOT is

a trademark of Linear Technology Corporation. All other trademarks are the property of

their respective owners.

Selectable Reset Timeout Period

BATTERY

POWERED

SYSTEM

LOGIC

2934 TA01a

0.1μF

PFO

RST

MR

LTC2934-2

GND

RT

ADJ

PFI

750k

11.8k

237k

POWER FAIL FALLING THRESHOLD = 1.686V

RESET FALLING THRESHOLD

= 1.606V

RST, RT = GND

15ms

200ms

2934 TA01b