Datasheet

LTC692/LTC693
3
0692fb
ELECTRICAL CHARACTERISTICS
PARAMETER CONDITIONS MIN TYP MAX UNITS
Battery Backup Switching
Operating Voltage Range
V
CC
V
BATT
4.50
2.00
5.50
4.00
V
V
V
OUT
Output Voltage I
OUT
= 1mA
l
V
CC
– 0.05
V
CC
– 0.10
V
CC
– 0.005
V
CC
– 0.005
V
V
I
OUT
= 50mA V
CC
– 0.50 V
CC
– 0.250 V
V
OUT
in Battery Backup 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
l
0.6
0.6
1.5
2.5
mA
mA
Supply Current in Battery Backup Mode V
CC
= 0V, V
BATT
= 2.8V
l
0.04
0.04
1
5
μA
μA
Battery Standby Current
(+ = Discharge, – = Charge)
5.5V > V
CC
> V
BATT
+ 0.2V
l
–0.1
–1.0
0.02
0.10
μA
μA
Battery Switchover Threshold
V
CC
– V
BATT
Power Up
Power Down
70
50
mV
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
BATT ON = 0V, Source Current 0.5
35
125
mA
μA
Reset and Watchdog Timer
Reset Voltage Threshold
l
4.25 4.40 4.50 V
Reset Threshold Hysteresis 40 mV
Reset Active Time
(Note 5)
OSC SEL High, V
CC
= 5V
l
160
140
200
200
240
280
ms
ms
The l denotes the specifi cations which apply over the full operating
temperature range, otherwise specifi cations are at T
A
= 25°C. V
CC
= full operating range, V
BATT
= 2.8V, unless otherwise noted.
PRODUCT SELECTION GUIDE
PINS
RESET
THRESHOLD
(V)
WATCHDOG
TIMER
BATTERY
BACKUP
POWER-FAIL
WARNING
RAM WRITE-
PROTECT
PUSHBUTTON
RESET
CONDITIONAL
BATTERY
BACKUP
LTC692 8 4.40 X X X
LTC693 16 4.40 X X X X
LTC690 8 4.65 X X X
LTC691 16 4.65 X X X X
LTC694 8 4.65 X X X
LTC695 16 4.65 X X X X
LTC699 8 4.65 X
LTC1232 8 4.37/4.62 X X
LTC1235 16 4.65 X X X X X X
LTC694-3.3 8 2.90 X X X
LTC695-3.3 16 2.90 X X X X