Datasheet

LTC1235
5
1235fa
TYPICAL PERFORMANCE CHARACTERISTICS
RESET Output Voltage vs
SupplyVoltage
Reset Active Time vs
Temperature
Reset Voltage Threshold vs
Temperature
Power Fail Comparator
Response Time
Power Fail Comparator
Response Time
Power Fail Comparator Response
Time with Pullup Resistor
V
OUT
vs I
OUT
V
OUT
vs I
OUT
Power Failure Input Threshold
vs Temperature
LOAD CURRENT (mA)
0
OUTPUT VOLTAGE (V)
4.90
4.95
5.00
40
1235 G01
4.85
4.80
4.75
10
20
30
50
SLOPE = 5Ω
V
CC
= 5V
V
BATT
= 2.8V
T
A
= 25°C
LOAD CURRENT (μA)
0
OUTPUT VOLTAGE (V)
2.76
2.78
400
1235 G02
2.74
2.72
100
200
300
500
2.80
BACKUP MODE
SELECTED
V
CC
= 0V
V
BATT
= 2.8V
T
A
= 25°C
SLOPE = 125Ω
TEMPERATURE (˚C)
–50
PFI INPUT THRESHOLD (V)
1.304
1.306
1.308
25 75
1235 G03
1.302
1.300
–25 0
50 100 125
1.298
1.296
1.294
V
CC
= 5V
SUPPLY VOLTAGE (V)
0
RESET OUTPUT VOLTAGE (V)
3
4
5
4
2
1
0
1
2
3
5
T
A
= 25°C
EXTERNAL PULLUP = 10μA
V
BATT
= 0V
1235 G04
TEMPERATURE (°C)
–50
RESET ACTIVE TIME (ms)
216
224
232
25 75
1235 G05
208
200
–25 0
50 100 125
192
184
V
CC
= 5V
TEMPERATURE (°C)
–50
RESET VOLTAGE THRESHOLD (V)
4.64
4.65
4.66
25 75
1235 G06
4.63
4.62
–25 0
50 100 125
4.61
4.60
TIME (μs)
0
4
5
6
4
1235 G07
3
2
0
123
5
1
1.305V
1.285V
87
6
V
CC
= 5V
T
A
= 25°C
+
–
V
PFI
1.3V
PFO
30pF
V
PFI
= 20mV STEP
PFO OUTPUT VOLTAGE (V)
TIME (μs)
0
4
5
6
40
1235 G08
3
2
0
20
60
1
1.315V
1.295V
120
10080
V
PFI
= 20mV STEP
180160
140
V
CC
= 5V
T
A
= 25°C
+
–
V
PFI
1.3V
PFO
30pF
PFO OUTPUT VOLTAGE (V)
TIME (μs)
0
4
5
6
4
1235 G09
3
2
0
2
6
1
1.315V
1.295V
12
108
V
PFI
= 20mV STEP
1816
14
V
CC
= 5V
T
A
= 25°C
+
–
V
PFI
1.3V
PFO
30pF
10k
+5V
PFO OUTPUT VOLTAGE (V)