Datasheet

LT3015 Series
12
3015fb
TYPICAL PERFORMANCE CHARACTERISTICS
T
A
= 25°C, unless otherwise noted.
LT3015 10Hz to 100kHz Output
Noise, C
FF
= 10nF
V
OUT
200µV/DIV
C
OUT
= 10µF
V
OUT
= –5V
I
L
= –1.5A
C
FF
= 10nF
3015 G49
1ms/DIV
SHDN Transient Response,
I
L
= –5mA, C
FF
= 0
SHDN Transient Response,
I
L
= –1.5A, C
FF
= 0
V
SHDN
1V/DIV
V
OUT
2V/DIV
R
L
= 1kΩ
C
OUT
= 10µF
V
OUT
= –5V
C
FF
= 0
3015 G50
25ms/DIV
V
SHDN
1V/DIV
V
OUT
2V/DIV
R
L
= 3.3Ω
C
OUT
= 10µF
V
OUT
= –5V
C
FF
= 0
3015 G51
250µs/DIV
Start-Up Time vs C
FF
LT3015 Transient Response,
C
OUT
= 10µF
FEEDFORWARD CAPACITOR, C
FF
(F)
100p 1n 10n
0.001
0.01
0.1
1.0
10
START-UP TIME (mS)
100
100n
3015 G53
I
L
= –1.5A
I
FB-DIVIDER
= 100µA
T
J
= 25°C
V
OUT
= –1.22V
V
OUT
= –5V
V
OUT
= –3V
V
OUT
= –12V
V
OUT
= –15V
V
OUT
100mV/DIV
I
OUT
1A/DIV
C
OUT
= 10µF
V
OUT
= –1.22V
V
IN
= –3V
∆I
OUT
= –50mA TO –1.5A
3015 G54
25µs/DIV
SHDN Transient Response,
I
L
= –1.5A, C
FF
= 10nF
V
SHDN
1V/DIV
V
OUT
2V/DIV
R
L
= 3.3Ω
C
OUT
= 10µF
V
OUT
= –5V
C
FF
= 10nF
3015 G52
250µs/DIV
RMS Output Noise
vs Feedforward Capacitor (C
FF
)
LT3015 10Hz to 100kHz Output
Noise
LT3015 10Hz to 100kHz Output
Noise, C
FF
= 0
FEEDFORWARD CAPACITANCE, C
FF
(F)
10p 100p 1n 10n 100n
0
25
50
75
100
OUTPUT NOISE (µV
RMS
)
125
150
175
200
225
250
1µ
3015 G46
I
L
= –1.5A
C
OUT
= 10µF
f = 10Hz TO 100kHz
I
FB-DIVIDER
= 100µA
T
J
= 25°C
V
OUT
= –5V
V
OUT
= –1.22V
V
OUT
100µV/DIV
C
OUT
= 10µF
V
OUT
= –1.22V
I
L
= –1.5A
3015 G47
1ms/DIV
V
OUT
200µV/DIV
C
OUT
= 10µF
V
OUT
= –5V
I
L
= –1.5A
C
FF
= 0
3015 G48
1ms/DIV