Datasheet

3
LTC1643AL
LTC1643AL-1/LTC1643AH
1643afb
DC
ELECTRICAL CHARACTERISTICS
TYPICAL PERFORMANCE CHARACTERISTICS
UW
3.3V and 5V Current
Foldback Profile
OUTPUT VOLTAGE (V)
0
OUTPUT CURRENT (A)
11
10
9
8
7
6
5
4
3
2
1
0
4
1643A G01
1
2
3
5
R
SENSE
= 0.005Ω
3V
OUT
5V
OUT
OUTPUT VOLTAGE (V)
0
OUTPUT CURRENT (A)
1.0
0.5
0
–8 –10
1643A G03
–2
–4
–6
–12
OUTPUT VOLTAGE (V)
0
OUTPUT CURRENT (A)
1.0
0.5
0
810
1643A G02
2
4
6
12
12V Current Foldback Profile –12V Current Foldback Profile
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
TH
Power-Good Threshold Voltage V
3VOUT
0°C ≤ T
A
≤ 70°C ● 2.8 2.9 3.0 V
–40°C ≤ T
A
≤ 85°C ● 2.75 2.9 3.0 V
V
5VOUT
0°C ≤ T
A
≤ 70°C ● 4.5 4.65 4.75 V
–40°C ≤ T
A
≤ 85°C ● 4.4 4.65 4.75 V
V
IL
Input Low Voltage ON/ON, FAULT ● 0.8 V
V
IH
Input High Voltage ON/ON, FAULT ● 2V
V
OL
Output Low Voltage FAULT, PWRGD, I = 3mA ● 0.4 V
I
IN
ON/ON Pin Input Current ON/ON = GND ● ± 0.08 ±10 µA
ON/ON= 12V
IN
● ± 0.08 ±10 µA
5V
SENSE
Input Current 5V
SENSE
= 5V ● 50 100 µA
3V
SENSE
Input Current 3V
SENSE
= 3V ● 50 100 µA
5V
IN
Input Current 5V
IN
= 5V ● 460 700 µA
3V
IN
Input Current 3V
IN
= 3V ● 320 600 µA
5V
OUT
Input Current 5V
OUT
= 5V, ON = 3V, ON = GND ● 240 500 µA
3V
OUT
Input Current 3V
OUT
= 3.3V, ON = 3V, ON = GND ● 220 500 µA
R
DIS
5V
OUT
Discharge Impedance ON = GND or ON = 3V 100 Ω
3V
OUT
Discharge Impedance ON = GND or ON = 3V 70 Ω
12V
OUT
Discharge Impedance ON = GND or ON = 3V 450 Ω
V
EEOUT
Discharge Impedance ON = GND or ON = 3V 1600 Ω
I
TIMER
TIMER Pin Current Timer On, V
TIMER
= GND ● –15 –22 –27 µA
Timer Off, V
TIMER
= 5V 45 mA
V
TIMER
TIMER Threshold Voltage (V
12VIN
– V
TIMER
) ● 0.5 0.9 1.3 V
Note 2: All currents into device pins are positive; all currents out of device
pins are negative. All voltages are referenced to ground unless otherwise
specified.
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are T
A
= 25°C.
V
12VIN
= 12V, V
EEIN
= –12V, V
3VIN
= 3.3V, V
5VIN
= 5V (Note 2)