LP2950 / LP2951
CORPORATION
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
LP2951 MINIMUM
OPERATING VOLTAGE
LP2951 FEEDBACK
BIAS CURRENT
LP2951 FEEDBACK
PIN CURRENT
2.2
2.1
2.0
1.9
1.8
1.7
1.6
20
10
50
0
PIN 7 DRIVEN BY
EXTERNAL SOURCE
(REGULATROR RUN
OPEN LOOP)
–50
0
T
= 125˚C
A
–100
–150
–200
–250
–10
–20
–30
T
= 25˚C
A
T
= –55˚C
A
–75 –50 –25
0
25 50 75 100 125 150
–75 –50 –25
0
25 50 75 100 125 150
–2.0 –1.5 –1.0 –0.5
0
0.5
1.0
TEMPERATURE (˚C)
TEMPERATURE (˚C)
FEEDBACK VOLTAGE (V)
1D-34
1D-35
1D-36
LP2951 ERROR
LP2951 COMPARATOR
SINK CURRENT
LINE TRANSIENT
RESPONSE
COMPARATOR OUTPUT
8
6
2.5
2.0
1.5
1.0
0.5
0.0
100mV
50mV
0
V
= 5V
OUT
T
= 125˚C
A
4
T
= 25˚C
A
C
I
= 1µA
L
–50mV
8V
HYSTERESIS
= 1mA
L
2
V
= 5V
OUT
T
= –55˚C
A
0
6V
NOTE: PULLUP RESISTOR
TO SEPARATE 5V SUPPLY
–2
4V
0
1
2
3
4
5
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
0
200
400
600
800
INPUT VOLTAGE (V)
OUTPUT LOW VOLTAGE (V)
TIME (µs)
1D-37
1D-38
1D-39
OUTPUT IMPEDANCE
RIPPLE REJECTION
RIPPLE REJECTION
10
5
90
80
70
60
50
40
30
20
90
80
70
60
50
40
30
20
C
= 1µF
L
I
= 100µA
V
= 6V
= 5V
O
IN
V
2
1
OUT
I
= 1mA
I
= 100mA
O
O
I
= 1mA
L
I
= 0
L
0.5
0.2
0.1
V
= 5V
OUT
= 1µA
I
= 100µA
L
C
L
C
V
V
1
= 1µF
0.05
L
= 6V
IN
0.02
0.01
I
= 10mA
L
= 5V
2
OUT
3
4
5
6
1
2
3
4
5
6
10
10
100
1K
10K
100K
1M
10
10
10
10
10
10
10
10
10
10
10
FREQUENCY (Hz)
FREQUENCY (Hz)
FREQUENCY (Hz)
1D-40
1D-41
1D-42
LP2951
LOAD TRANISENT
RESPONSE
LOAD TRANSIENT
RESPONSE
ENABLE TRANSIENT
7
6
250
80
60
C
= 1µF
L
200
150
100
50
40
5
20
4
I
= 10mA
L
0
3
V
V
= 8V
IN
OUT
0
–20
–40
–60
2
C
= 10µF
= 5V
L
–50
–100
1
C
V
= 1µF
C
V
= 10µF
L
L
0
= 5V
= 5V
OUT
OUT
2
100mA
100mA
0
100µA
100µA
–2
–100
0
100 200 300 400 500 600 700
0
1
2
3
4
5
0
4
8
12
16
20
TIME (µs)
1D-45
TIME (ms)
TIME (ms)
1D-43
1D-44
CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025
CALOGIC [ CALOGIC, LLC ]
