LM2672
LM2672-ADJ
Symbol
η
(Continued)
Conditions
V
IN
= 12V, I
LOAD
= 1A
Typ
90
Min
Max
%
Units
Parameter
Efficiency
All Output Voltage Versions
Electrical Characteristics
Specifications with standard type face are for T
J
= 25˚C, and those in
bold type face
apply over
full Operating Temperature
Range.
Unless otherwise specified, V
IN
= 12V for the 3.3V, 5V, and Adjustable versions and V
IN
= 24V for the 12V version,
and I
LOAD
= 100 mA.
Symbol
I
Q
Parameters
Quiescent Current
Conditions
V
FEEDBACK
= 8V
For 3.3V, 5.0V, and ADJ Versions
V
FEEDBACK
= 15V
For 12V Versions
I
STBY
I
CL
I
L
Standby Quiescent Current
Current Limit
Output Leakage Current
V
IN
= 40V, ON/OFF Pin = 0V
V
SWITCH
= 0V
V
SWITCH
= −1V, ON/OFF Pin = 0V
R
DS(ON)
f
O
D
I
BIAS
V
S/D
I
S/D
F
SYNC
V
SYNC
V
SS
I
SS
θ
JA
Switch On-Resistance
Oscillator Frequency
Maximum Duty Cycle
Minimum Duty Cycle
Feedback Bias
Current
ON/OFF Pin
Voltage Thesholds
ON/OFF Pin Current
Synchronization Frequency
Synchronization Threshold
Voltage
Soft-Start Voltage
Soft-Start Current
Thermal Resistance
N Package, Junction to Ambient (Note 6)
M Package, Junction to Ambient (Note 6)
ON/OFF Pin = 0V
V
SYNC
= 3.5V, 50% duty cycle
20
400
1.4
0.63
4.5
95
105
0.53
1.5
0.73
6.9
7
37
µA
kHz
V
V
µA
˚C/W
V
FEEDBACK
= 1.3V
ADJ Version Only
1.4
0.8
2.0
V
I
SWITCH
= 1A
Measured at Switch Pin
6
0.25
260
95
0
85
225
15
0.30/0.50
275
mA
Ω
kHz
%
%
nA
ON/OFF Pin = 0V
50
1.55
1
1.25/1.2
100/150
2.1/2.2
25
µA
A
µA
2.5
mA
Typ
2.5
Min
Max
3.6
Units
mA
DEVICE PARAMETERS
Note 1:
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is
intended to be functional, but device parameter specifications may not be guaranteed under these conditions. For guaranteed specifications and test conditions, see
the Electrical Characteristics.
Note 2:
The human body model is a 100 pF capacitor discharged through a 1.5 kΩ resistor into each pin.
Note 3:
External components such as the catch diode, inductor, input and output capacitors, and voltage programming resistors can affect switching regulator
performance. When the LM2672 is used as shown in
and
test circuits, system performance will be as specified by the system parameters section
of the Electrical Characteristics.
Note 4:
Typical numbers are at 25˚C and represent the most likely norm.
Note 5:
All limits guaranteed at room temperature (standard type face) and at
temperature extremes (bold type face).
All room temperature limits are 100%
production tested. All limits at
temperature extremes
are guaranteed via correlation using standard Statistical Quality Control (SQC) methods. All limits are used
to calculate Average Outgoing Quality Level (AOQL).
Note 6:
Junction to ambient thermal resistance with approximately 1 square inch of printed circuit board copper surrounding the leads. Additional copper area will
lower thermal resistance further. See Application Information section in the application note accompanying this datasheet and the thermal model in
LM267X Made
Simple
version 1.0 software.
3
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