LTC2934
5
2934f
Supply Current vs RT
Input Voltage
Supply Current vs MR Input Voltage
PIN FUNCTIONS
ADJ: Reset Threshold Adjustment Input. Tie to resistive
divider between monitored voltage and GND to confi gure
desired reset threshold. See the Applications Information
section for details. Tie to V
CC
if unused.
Exposed Pad (DFN Only): Exposed Pad may be left fl oating
or connected to device ground.
GND: Device Ground.
MR: Manual Reset Input. Attach a push-button switch
between this input and ground. A logic low on this input
pulls RST low. When the MR input returns to logic high,
RST returns high after the reset timer has expired. Tie to
V
CC
if unused.
PFI: Power-Fail Threshold Adjustment Input. Tie to
resistive divider between monitored voltage and GND
to configure desired power-fail threshold. See the
Applications Information section for details. Tie to V
CC
or
GND if unused.
PFO: Power-Fail Output. PFO pulls low when monitored
voltage falls below the power-fail (PFI) threshold. PFO
is released when the PFI voltage rises above the power-
fail threshold by 2.5%. PFO is available with open-drain
(LTC2934-1) or active pull-up (LTC2934-2) outputs. Leave
open if unused.
RST: Reset Output. RST pulls low when monitored volt-
age falls below the reset threshold. RST is released after
monitored voltage exceeds the reset threshold plus 5%
hysteresis and after reset timer has expired. RST is available
with open-drain (LTC2934-1) or active pull-up (LTC2934-2)
outputs. Leave open if unused.
RT: Reset Timeout Selection Input. Tie to GND or V
CC
for
desired reset timeout. Tie low for 15ms delay or high for
200ms delay.
V
CC
: Power Supply Input. Bypass V
CC
with 0.1μF to
GND.
TYPICAL PERFORMANCE CHARACTERISTICS
RT INPUT VOLTAGE (V)
0
I
CC
(μA)
200
3.5
150
100
12
0.5
1.5 2.5 3 4
50
0
250
2934 G07
V
CC
= 3.6V
MR INPUT VOLTAGE (V)
0
I
CC
(μA)
4
3.5
3
2
12
0.5
1.5 2.5 3 4
1
0
5
2934 G08
V
CC
= 3.6V
T
A
= 25°C, unless otherwise noted.