
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
V
IN Pin: Voltage to GND
0.2V to 6.0V
EN, FB, SW Pin:
(GND0.2V) to
(V
IN + 0.2V)
Continuous Power Dissipation
Internally Limited
Junction Temperature (T
J-MAX)
+125C
Storage Temperature Range
65C to +150C
Maximum Lead Temperature
(Soldering, 10 sec.)
260C
Human Body model: All Pins
2 kV
Machine Model: All Pins
200V
Operating Ratings (Notes 1, 2) Input Voltage Range (Note 11)
2.7V to 5.5V
Recommended Load Current
0A to 600 mA
Junction Temperature (T
J) Range
30C to +125C
Ambient Temperature (T
A) Range
30C to +85C
Thermal Properties
Junction-to-Ambient
Thermal Resistance (
θ
JA)
(SOT23-5) for a 2 layer
board (Note 6)
Junction-to-Ambient
Thermal Resistance (
θ
JA)
(SOT23-5) for a 4 layer
board (Note 6)
250C/W
130C/W
Electrical Characteristics (Notes 2, 9, 10) Limits in standard typeface are for T
J = 25C. Limits in boldface
type apply over the full operating junction temperature range (30C
≤ T
J
≤ 125C). Unless otherwise noted, specifications
apply to the LM3674 with V
IN = EN = 3.6V
Symbol
Parameter
Condition
Min
Typ
Max
Units
V
FB
Feedback Voltage (Note 12, 13)
I
O = 10mA
-4
+4
%
Line Regulation
2.7V
≤ V
IN
≤ 5.5V
I
O = 100 mA
0.083
%/V
Load Regulation
100 mA
≤ I
O
≤ 600 mA
V
IN = 3.6V
0.0010
%/mA
V
REF
Internal Reference Voltage
(Note 7)
0.5
V
I
SHDN
Shutdown Supply Current
EN = 0V
0.01
1
A
I
Q
DC Bias Current into V
IN
No load, device is not
switching (FB=0V)
300
600
A
R
DSON (P)
Pin-Pin Resistance for PFET
I
SW = 200mA
380
500
m
R
DSON (N)
Pin-Pin Resistance for NFET
I
SW = 200mA
250
400
m
I
LIM
Switch Peak Current Limit
Open Loop (Note 8)
830
1020
1200
mA
V
IH
Logic High Input
1.0
V
IL
Logic Low Input
0.4
V
I
EN
Enable (EN) Input Current
0.01
1
A
F
OSC
Internal Oscillator Frequency
PWM Mode
1.6
2
2.6
MHz
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings are conditions under which operation of the
device is guaranteed. Operating Ratings do not imply guaranteed performance limits. For guaranteed performance limits and associated test conditions, see the
Electrical Characteristics tables.
Note 2: All voltages are with respect to the potential at the GND pin.
Note 3: The Human body model is a 100 pF capacitor discharged through a 1.5 k
resistor into each pin. The machine model is a 200 pF capacitor discharged
directly into each pin (MIL-STD-883 3015.7). National Semiconductor recommends that all intergrated circuits be handled with appropriate precautions. Failure to
observe proper ESD handling techniques can result in damage.
Note 4: Internal thermal shutdown circuitry protects the device from permanent damage. Thermal shutdown engages at TJ = 150C (typ.) and disengages at TJ =
130C
Note 5: In Applications where high power dissipation and /or poor package resistance is present, the maximum ambient temperature may have to be derated.
Maximum ambient temperature (TA-MAX ) is dependent on the maximum operating junction temperature (TJ-MAX ), the maximum power dissipation of the device in
the application (PD-MAX ) and the junction to ambient thermal resistance of the package (θJA) in the application, as given by the following equation: TA-MAX =TJ-MAX-
(
θJA xPD-MAX). Refer to Dissipation ration table for PD-MAX values at different ambient temperatures.
Note 6: Junction to ambient thermal resistance is highly application and board layout dependent. In applications where high power dissipation exists, special care
must be given to thermal dissipation issues in board design. Value specified here 250C/W is based on measurement results using a 2 layer, 4" X 3", 2 oz. Cu board
as per JEDEC standards. The (
θJA) is 130C/W if a 4 layer, 4" X 3", 2/1/1/2 oz. Cu board as per JEDEC standards is used.
Note 7: For the ADJ version the resistor dividers should be selected such that at the desired output voltage, the voltage at the FB pin is 0.5V.
Note 8: Refer to datasheet curves for closed loop data and its variation with regards to supply voltage and temperature. Electrical Characteristic table reflects open
loop data (FB=0V and current drawn from SW pin ramped up until cycle by cycle current limit is activated). Closed loop current limit is the peak inductor current
measured in the application circuit by increasing output current until output voltage drops by 10%.
Note 9: Min and Max limits are guaranteed by design, test or statistical analysis. Typical numbers are not guaranteed, but do represent the most likely norm.
Note 10: The parameters in the electrical characteristic table are tested at VIN = 3.6V unless otherwise specified. For performance over the input voltage range refer
to datasheet curves.
LM3674
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