Preliminary
RT9701B
Soft - start Short Circuit Response
CH1: V
IN
: 2V/Div
Inrush Short Circuit Response
CH1: V
IN
: 2V/Div
V
DROP
=1.2V, depend on C
IN
ESR
I
PEAK
: depend on ESR & ESL
CH1
CH1
CH2: I
L
: 1A/Div
CH2
CH2: I
L
: 1A/Div
C
IN
= 1uF, C
OUT
= 1000uF
CH2
C
IN
= 1uF
Time (25us/Div)
Time (50us/Div)
Ramped Load Response
CH1
V
OUT
=
4.9V
Current Limit Threshold
V
OUT
= 4.6V
Thermal Shut Dowm Response
CH1
CH3
1.1A
Thermal Shut Down
CH2
CH2
CH2: I
OUT
: 500mA/Div
V
IN
= 5V, C
OUT
= 1uF
CH1: V
EN
= 5V/Div, CH3:I
OUT
@R
L
1Ω:1A/Div
CH2: I
OUT
@short:1A/DiV, V
IN
= 5V
Time (1ms/Div)
Time (50ms/Div)
Current Limit Response
Current Limit Response
C
OUT
= 1uF
C
OUT
= 33uF
C
OUT
= 100uF
C
OUT
= 1uF
C
OUT
= 33uF
C
OUT
= 100uF
I
OUT
(1A/Div)
V
IN
= 5V,
R
L
= 1Ω
I
L
(1A/Div)
V
IN
= 5V,
R
L
= 1Ω
Time (100us/Div)
Time (100us/Div)
DS9701B-04 March 2007
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