Datasheet

LTC3835
3
3835fd
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Main Control Loops
V
FB
Regulated Feedback Voltage (Note 4); I
TH
Voltage = 1.2V
l
0.792 0.800 0.808 V
I
VFB
Feedback Current (Note 4) –5 –50 nA
V
REFLNREG
Reference Voltage Line Regulation V
IN
= 4V to 30V (Note 4) 0.002 0.02 %/V
V
LOADREG
Output Voltage Load Regulation (Note 4)
Measured in Servo Loop; ∆I
TH
Voltage = 1.2V to 0.7V
Measured in Servo Loop; ∆I
TH
Voltage = 1.2V to 2V
l
l
0.1
– 0.1
0.5
–0.5
%
%
g
m
Transconductance Amplifier g
m
I
TH
= 1.2V; Sink/Source 5µA (Note 4) 1.55 mmho
I
Q
Input DC Supply Current
Sleep Mode
Shutdown
(Note 5)
RUN = 5V, V
FB
= 0.83V (No Load)
V
RUN
= 0V
80
10
125
20
µA
µA
UVLO Undervoltage Lockout V
IN
Ramping Down
l
3.5 4 V
V
OVL
Feedback Overvoltage Lockout Measured at V
FB
Relative to Regulated V
FB
8 10 12 %
I
SENSE
Sense Pins Total Source Current V
SENSE
– = V
SENSE
+ = 0V –660 µA
DF
MAX
Maximum Duty Factor In Dropout 98 99.4 %
I
TRACK/SS
Soft-Start Charge Current V
TRACK
= 0V 0.75 1.0 1.35 µA
V
RUN
ON RUN Pin ON Threshold V
RUN
Rising 0.5 0.7 0.9 V
V
SENSE(MAX)
Maximum Current Sense Threshold V
FB
= 0.7V, V
SENSE
– = 3.3V
V
FB
= 0.7V, V
SENSE
– = 3.3V
l
90
80
100
100
110
115
mV
mV
TG t
r
TG t
f
TG Transition Time:
Rise Time
Fall Time
(Note 6)
C
LOAD
= 3300pF
C
LOAD
= 3300pF
50
50
90
90
ns
ns
BG t
r
BG t
f
BG Transition Time:
Rise Time
Fall Time
(Note 6)
C
LOAD
= 3300pF
C
LOAD
= 3300pF
40
40
90
80
ns
ns
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 12V, V
RUN
= 5V unless otherwise noted.
ORDER INFORMATION
LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC3835EFE#PBF LTC3835EFE#TRPBF LTC3835EFE 20-Lead Plastic TSSOP –40°C to 85°C
LTC3835IFE#PBF LTC3835IFE#TRPBF LTC3835IFE 20-Lead Plastic TSSOP –40°C to 85°C
LTC3835EUFD#PBF LTC3835EUFD#TRPBF 3835 20-Pin (4mm × 5mm) Plastic DFN –40°C to 85°C
LTC3835IUFD#PBF LTC3835IUFD#TRPBF 3835 20-Pin (4mm × 5mm) Plastic DFN –40°C to 85°C
LEAD BASED FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC3835EFE LTC3835EFE#TR LTC3835EFE 20-Lead Plastic TSSOP –40°C to 85°C
LTC3835IFE LTC3835IFE#TR LTC3835IFE 20-Lead Plastic TSSOP –40°C to 85°C
LTC3835EUFD LTC3835EUFD#TR 3835 20-Pin (4mm × 5mm) Plastic DFN –40°C to 85°C
LTC3835IUFD LTC3835IUFD#TR 3835 20-Pin (4mm × 5mm) Plastic DFN –40°C to 85°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
For more information on lead free part marking, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/
(Note 2)