LTC2935
5
2935fa
Supply Current vs S0, S1, S2
Input Voltage
Supply Current vs MR Input Voltage
PIN FUNCTIONS
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 pushbutton 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 200ms. Tie to V
CC
if unused.
PFO: Power-Fail Output. PFO pulls low when V
CC
falls
below the power-fail threshold. The power-fail thresh-
old is above the confi gured falling reset threshold by a
pre-determined margin. PFO is released when V
CC
rises
above the power-fail threshold by 2.5%. PFO is available
with open-drain (LTC2935-1/LTC2935-3) or active pull-up
(LTC2935-2/LTC2935-4) outputs. Leave open if unused.
RST: Reset Output. RST pulls low when V
CC
falls below the
reset threshold. RST is released 200ms after V
CC
exceeds
the reset threshold plus 5% hysteresis. RST is available
with open-drain (LTC2935-1/LTC2935-3) or active pull-up
(LTC2935-2/LTC2935-4) outputs. Leave open if unused.
S2, S1, S0: Threshold Selection Inputs. Tie to GND or
V
CC
for required reset threshold. See the Falling Threshold
Selection Table on page 1 for settings.
V
CC
: Power Supply and Monitored Voltage Input. Bypass
V
CC
with a 0.1μF capacitor to GND.
TYPICAL PERFORMANCE CHARACTERISTICS
S0, S1, S2 INPUT VOLTAGE (V)
0
I
CC
(μA)
200
3.5
150
100
12
0.5
1.5 2.5 3 4
50
0
250
2935 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
2935 G08
V
CC
= 3.6V
T
A
= 25°C, unless otherwise noted.
