Datasheet

3
LTC690/LTC691
LTC694/LTC695
E
LECTR
IC
AL C CHARA TERIST
ICS
The ● denotes specifications which apply over the operating temperature
range, otherwise specifications are at T
A
= 25°C. V
CC
= full operating range, V
BATT
= 2.8V, unless otherwise noted.
PARAMETER CONDITONS MIN TYP MAX UNITS
Battery Back-Up Switching
Operating Voltage Range V
CC
4.75 5.50 V
V
BATT
2.00 4.25 V
V
OUT
Output Voltage I
OUT
= 1mA V
CC
– 0.05 V
CC
– 0.005 V
● V
CC
– 0.10 V
CC
– 0.005 V
I
OUT
= 50mA V
CC
– 0.50 V
CC
– 0.250 V
V
OUT
in Battery Back-Up Mode I
OUT
= 250µA, V
CC
< V
BATT
V
BATT
– 0.1 V
BATT
– 0.02 V
Supply Current (Exclude I
OUT
)I
OUT
≤ 50mA 0.6 1.5 mA
● 0.6 2.5 mA
Supply Current in Battery Back-Up Mode V
CC
= 0V, V
BATT
= 2.8V 0.04 1 µA
● 0.04 5 µA
Battery Standby Current (+ = Discharge, – = Charge) 5.5 > V
CC
> V
BATT
+ 0.2V –0.1 +0.02 µA
● –1.0 +0.10 µA
Battery Switchover Threshold, V
CC
– V
BATT
Power Up 70 mV
Power Down 50 mV
Battery Switchover Hysteresis 20 mV
BATT ON Output Voltage (Note 4) I
SINK
= 3.2mA 0.4 V
BATT ON Output Short-Circuit Current (Note 4) BATT ON = V
OUT
Sink Current 35 m
BATT ON = 0V Source Current 0.5 1 25 µA
Reset and Watchdog Timer
Reset Voltage Threshold ● 4.5 4.65 4.75 V
LTC690M ● 4.4 4.65 4.75 V
Reset Threshold Hysteresis 40 mV
Reset Active Time (LTC690/91) (Note 5) OSC SEL HIGH, V
CC
= 5V 40 50 60 ms
● 35 50 70 ms
Reset Active Time (LTC694/95) (Note 5) OSC SEL HIGH, V
CC
= 5V 160 200 240 ms
● 140 200 280 ms
Watchdog Time-Out Period, Internal Oscillator Long Period, V
CC
= 5V 1.2 1.6 2.00 sec
● 1.0 1.6 2.25 sec
Short Period, V
CC
= 5V 80 100 120 ms
● 70 100 140 ms
Watchdog Time-Out Period, External Clock (Note 6) Long Period 4032 4097 Clock
Short Period 960 1025 Cycles
Reset Active Time PSRR 1 ms/V
Watchdog Time-Out Period PSRR, Internal OSC 1 ms/V
Minimum WDI Input Pulse Width V
IL
= 0.4V, V
IH
= 3.5V ● 200 ns
RESET Output Voltage at V
CC
= 1V I
SINK
= 10µA, V
CC
= 1V 4 200 mV
RESET and LOW LINE Output Voltage (Note 4) I
SINK
= 1.6mA, V
CC
= 4.25V 0.4 V
I
SOURCE
= 1µA, V
CC
= 5V 3.5 V
RESET and WDO Output Voltage (Note 4) I
SINK
= 1.6mA, V
CC
= 5V 0.4 V
I
SOURCE
= 1µA, V
CC
= 4.25V 3.5 V