Datasheet

LTC3833
3
3833f
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating junction
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 15V, V
FB
= V
OSNS
+
– V
OSNS
–
, unless otherwise noted. (Note 4)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
General
V
IN
Input Voltage Operating Range 4.5 38 V
V
OUT
Output Voltage Operating Range 0.6 5.5 V
I
Q
Input DC Supply Current
Normal
Shutdown Supply Current
MODE/PLLIN = INTV
CC
RUN = 0V
2
15
4
25
mA
µA
t
ON(MIN)
Minimum On-Time V
IN
= 38V, V
OUT
= 0.6V 20 ns
t
OFF(MIN)
Minimum Off-Time 90 ns
Output Sensing
V
REG
Regulated Differential Feedback Voltage
(V
OSNS
+
– V
OSNS
–
)
ITH = 1.2V (Note 5)
T
A
= 25°C
T
A
= 0°C to 85°C
T
A
= –40°C to 125°C
l
l
0.5985
0.596
0.594
0.6
0.6
0.6
0.6015
0.604
0.606
V
V
V
Regulated Differential Feedback Voltage
Over Line, Load and Common Mode
(V
OSNS
+
– V
OSNS
–
)
V
IN
= 4.5V to 38V, ITH = 0.5V to 1.9V,
V
OSNS
–
= ±500mV (Note 5)
T
A
= 0°C to 85°C
T
A
= –40°C to 125°C
l
l
0.594
0.591
0.6
0.6
0.606
0.609
V
V
g
m(EA)
Error Amplifier Transconductance ITH = 1.2V (Note 5)
l
1.4 1.7 2 mS
I
VOSNS
+
V
OSNS
+
Input Bias Current V
FB
= 0.6V ±5 ±25 nA
I
VOSNS
–
V
OSNS
–
Input Bias Current V
FB
= 0.6V –35 –50 µA
Current Sensing
V
SENSE(MAX)
Valley Current Sense Threshold,
V
SENSE
+
– V
SENSE
–
,
Peak Current = Valley + Ripple
V
RNG
= 2V, V
FB
= 0.57V
V
RNG
= 0V, V
FB
= 0.57V
V
RNG
= INTV
CC
, V
FB
= 0.57V
l
l
l
80
22
39
100
30
50
120
38
61
mV
mV
mV
V
SENSE(MIN)
Minimum Current Sense Threshold,
V
SENSE
+
– V
SENSE
–
, Forced Continuous
Mode
V
RNG
= 2V, V
FB
= 0.63V
V
RNG
= 0V, V
FB
= 0.63V
V
RNG
= INTV
CC
, V
FB
= 0.63V
–50
–15
–25
mV
mV
mV
V
SENSE(CM)
SENSE
+
, SENSE
–
Voltage Range
(Common Mode)
Referenced to Signal Ground (SGND)
l
–0.5 5.5 V
I
SENSE
SENSE
+
, SENSE
–
Input Bias Current V
SENSE(CM)
= 0.6V
V
SENSE(CM)
= 5V
±5
1
±50
4
nA
µA
Start-Up and Shutdown
V
RUN(TH)
RUN Pin On Threshold V
RUN
Rising
l
1.1 1.2 1.3 V
V
RUN(HYS)
RUN Pin Hysteresis 70 mV
I
SS
Soft-Start Charging Current V
TRACK/SS
= 0V 1.0 µA
UVLO
LOCK
INTV
CC
Undervoltage Lockout INTV
CC
Falling
l
3.4 3.65 4.0 V
UVLO
RELEASE
INTV
CC
Undervoltage Lockout Release INTV
CC
Rising
l
4.2 4.5 V
Switching Frequency and Clock Synchronization
f Free Running Switching Frequency R
T
= 205k
R
T
= 80.6k
R
T
= 18.2k
175
450
1800
200
500
2000
225
550
2200
kHz
kHz
kHz
V
CLK(IH)
Clock Input High Level into MODE/PLLIN 2 V
V
CLK(IL)
Clock Input Low Level into MODE/PLLIN 0.5 V