3
LTC 690/LTC 691
LTC 694/LTC 695
ELECTRICAL C
range, otherwise specifications are at T
A
= 25
°
C. V
CC
= full operating range, V
BATT
= 2.8V, unless otherwise noted.
HARC
The
G
denotes specifications which apply over the operating temperature
PARAMETER
Battery Back-Up Switching
Operating Voltage Range
CONDITONS
MIN
TYP
MAX
UNITS
V
CC
V
BATT
I
OUT
= 1mA
4.75
2.00
5.50
4.25
V
V
V
V
V
V
V
OUT
Output Voltage
V
CC
– 0.05
V
CC
– 0.10
V
CC
– 0.50
V
BATT
– 0.1
V
CC
– 0.005
V
CC
– 0.005
V
CC
– 0.250
V
BATT
– 0.02
0.6
0.6
0.04
0.04
G
I
OUT
= 50mA
I
OUT
= 250
μ
A, V
CC
< V
BATT
I
OUT
≤
50mA
V
OUT
in Battery Back-Up Mode
Supply Current (Exclude I
OUT
)
1.5
2.5
1
5
+0.02
+0.10
mA
mA
μ
A
μ
A
μ
A
μ
A
mV
mV
mV
G
Supply Current in Battery Back-Up Mode
V
CC
= 0V, V
BATT
= 2.8V
G
Battery Standby Current (+ = Discharge, – = Charge)
5.5 > V
CC
> V
BATT
+ 0.2V
–0.1
–1.0
G
Battery Switchover Threshold, V
CC
– V
BATT
Power Up
Power Down
70
50
20
Battery Switchover Hysteresis
BATT ON Output Voltage (Note 4)
BATT ON Output Short-Circuit Current (Note 4)
I
SINK
= 3.2mA
BATT ON = V
OUT
Sink Current
BATT ON = 0V Source Current
0.4
V
m
μ
A
35
1
0.5
25
Reset and Watchdog Timer
Reset Voltage Threshold
G
4.5
4.4
4.65
4.65
40
50
50
200
200
1.6
1.6
100
100
4.75
4.75
V
V
LTC690M
G
Reset Threshold Hysteresis
Reset Active Time (LTC690/91) (Note 5)
mV
ms
ms
ms
ms
sec
sec
ms
ms
OSC SEL HIGH, V
CC
= 5V
40
35
160
140
1.2
1.0
80
70
4032
960
60
70
240
280
2.00
2.25
120
140
4097
1025
G
Reset Active Time (LTC694/95) (Note 5)
OSC SEL HIGH, V
CC
= 5V
G
Watchdog Time-Out Period, Internal Oscillator
Long Period, V
CC
= 5V
G
Short Period, V
CC
= 5V
G
Watchdog Time-Out Period, External Clock (Note 6)
Long Period
Short Period
Clock
Cycles
ms/V
ms/V
Reset Active Time PSRR
Watchdog Time-Out Period PSRR, Internal OSC
Minimum WDI Input Pulse Width
RESET Output Voltage at V
CC
= 1V
RESET and LOW LINE Output Voltage (Note 4)
1
1
V
IL
= 0.4V, V
IH
= 3.5V
I
SINK
= 10
μ
A, V
CC
= 1V
I
SINK
= 1.6mA, V
CC
= 4.25V
I
SOURCE
= 1
μ
A, V
CC
= 5V
I
SINK
= 1.6mA, V
CC
= 5V
I
SOURCE
= 1
μ
A, V
CC
= 4.25V
G
200
ns
mV
4
200
0.4
V
V
V
V
3.5
RESET and WDO Output Voltage (Note 4)
0.4
3.5