EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB
DD PACKAGE
8-LEAD (3mm
×
3mm) PLASTIC DFN
T
JMAX
= 125°C,
θ
JA
= 43°C/W,
θ
JC
= 3°C/W
EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB
orDer inForMaTion
LEAD FREE FINISH
LTC3631EMS8E#PBF
LTC3631EMS8E-3.3#PBF
LTC3631EMS8E-5#PBF
LTC3631IMS8E#PBF
LTC3631IMS8E-3.3#PBF
LTC3631IMS8E-5#PBF
LTC3631EDD#PBF
LTC3631EDD-3.3#PBF
LTC3631EDD-5#PBF
LTC3631IDD#PBF
LTC3631IDD-3.3#PBF
LTC3631IDD-5#PBF
TAPE AND REEL
LTC3631EMS8E#TRPBF
LTC3631EMS8E-3.3#TRPBF
LTC3631EMS8E-5#TRPBF
LTC3631IMS8E#TRPBF
LTC3631IMS8E-3.3#TRPBF
LTC3631IMS8E-5#TRPBF
LTC3631EDD#TRPBF
LTC3631EDD-3.3#TRPBF
LTC3631EDD-5#TRPBF
LTC3631IDD#TRPBF
LTC3631IDD-3.3#TRPBF
LTC3631IDD-5#TRPBF
PART MARKING*
LTFDT
LTFFP
LTFFR
LTFDT
LTFFP
LTFFR
LFDV
LFFN
LFFQ
LFDV
LFFN
LFFQ
PACKAGE DESCRIPTION
8-Lead Plastic MSOP
8-Lead Plastic MSOP
8-Lead Plastic MSOP
8-Lead Plastic MSOP
8-Lead Plastic MSOP
8-Lead Plastic MSOP
8-Lead (3mm
×
3mm) Plastic DFN
8-Lead (3mm
×
3mm) Plastic DFN
8-Lead (3mm
×
3mm) Plastic DFN
8-Lead (3mm
×
3mm) Plastic DFN
8-Lead (3mm
×
3mm) Plastic DFN
8-Lead (3mm
×
3mm) Plastic DFN
TEMPERATURE RANGE
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
Consult LTC Marketing for information on non-standard lead based finish parts.
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/
3631fe
2
For more information
www.linear.com/LTC3631
LTC3631
elecTrical characTerisTics
SYMBOL
V
IN
UVLO
PARAMETER
Input Voltage Operating Range
V
IN
Undervoltage Lockout
V
IN
Overvoltage Lockout
DC Supply Current (Note 3)
Active Mode
Sleep Mode
Shutdown Mode
Output Voltage Trip Thresholds
V
IN
Rising
V
IN
Falling
Hysteresis
V
IN
Rising
V
IN
Falling
Hysteresis
l
l
The
l
denotes the specifications which apply over the full operating
junction temperature range, otherwise specifications are for T
A
= 25°C (Note 2). V
IN
= 10V, unless otherwise noted.
CONDITIONS
MIN
4.5
3.80
3.75
47
45
4.15
4.00
150
50
48
2
125
12
3
l
l
l
l
l
l
TYP
MAX
45
4.50
4.35
52
50
UNITS
V
V
V
mV
V
V
V
µA
µA
µA
V
V
V
V
V
mV
nA
%/V
Input Supply (V
IN
)
OVLO
I
Q
V
RUN
= 0V
LTC3631-3.3V, V
OUT
Rising
LTC3631-3.3V, V
OUT
Falling
LTC3631-5V, V
OUT
Rising
LTC3631-5V, V
OUT
Falling
3.260
3.240
4.940
4.910
0.792
3
–10
220
22
6
3.360
3.340
5.090
5.060
0.808
7
10
Output Supply (V
OUT
/V
FB
)
V
OUT
3.310
3.290
5.015
4.985
0.800
5
0
0.001
V
FB
V
HYST
I
FB
∆V
LINEREG
Operation
V
RUN
I
RUN
V
HYSTL
I
HYST
I
SS
t
INTSS
I
PEAK
R
ON
Feedback Comparator Trip Voltage
Feedback Comparator Hysteresis
Feedback Pin Current
Feedback Voltage Line Regulation
V
FB
Rising
Adjustable Output Version, V
FB
= 1V
V
IN
= 4.5V to 45V
LTC3631-5, V
IN
= 6V to 45V
RUN Rising
RUN Falling
Hysteresis
RUN = 1.3V
RUN < 1V, I
HYST
= 1mA
V
HYST
= 1.3V
V
SS
< 1.5V
SS Pin Floating
I
SET
Floating
500k Resistor from I
SET
to GND
I
SET
Shorted to GND
I
SW
= –25mA
I
SW
= 25mA
Run Pin Threshold Voltage
1.17
1.06
–10
–10
4.5
l
1.21
1.10
110
0
0.07
0
5.5
0.75
225
120
50
3.0
1.5
1.25
1.14
10
0.1
10
6.5
280
65
V
V
mV
nA
V
nA
µA
ms
mA
mA
mA
Ω
Ω
Run Pin Leakage Current
Hysteresis Pin Voltage Low
Hysteresis Pin Leakage Current
Soft-Start Pin Pull-Up Current
Internal Soft-Start Time
Peak Current Trip Threshold
200
40
Power Switch On-Resistance
Top Switch
Bottom Switch
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2:
The LTC3631 is tested under pulsed load conditions such that
T
J
≈ T
A
. The LTC3631E is guaranteed to meet specifications from
0°C to 85°C junction temperature. Specifications over the –40°C to
125°C operating junction temperature range are assured by design,
characterization and correlation with statistical process controls. The
LTC3631I is guaranteed over the full –40°C to 125°C operating junction
temperature range. Note that the maximum ambient temperature
consistent with these specifications is determined by specific operating
conditions in conjunction with board layout, the rated package thermal
impedance and other environmental factors. The junction temperature
(T
J
, in °C) is calculated from the ambient temperature (T
A
, in °C) and power
dissipation (PD, in Watts) according to the formula:
T
J
= T
A
+ (PD •
θ
JA
)
where
θ
JA
(in °C/W) is the package thermal impedance.
Note 3:
Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency. See Applications Information.
