Switched-node connection, which is connected with the source of the internal high-side
MOSFET.
Main power supply pin.
Bootstrap capacitor connection for high-side gate drive.
Input supply voltage for control and driver circuits.
Shutdown and Soft-start control pin. Pulling this pin below 0.3V shuts off the regulator. A
capacitor connected from this pin to ground provides a control ramp of the input current.
Do not drive this pin with an external source or erroneous operation may result.
Output voltage feedback input. Connected to the output voltage.
Compensation network connection. Connected to the output of the voltage error amplifier.
No internal connection.
Low-noise analog ground.
Power ground.
9
10
11
12-13
14-16
FB
COMP
NC
AGND
PGND
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2
LM2651
Absolute Maximum Ratings
(Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Input Voltage
Feedback Pin Voltage
Power Dissipation (T
A
=25˚C),
(Note 2)
Junction Temperature Range
15V
−0.4V
≤
V
FB
≤
5V
893 mW
−40˚C
≤
T
J
≤
+125˚C
Storage Temperature Range
ESD Susceptibility
Human Body Model (Note 3)
−65˚C to +150˚C
1kV
Operating Ratings
(Note 1)
Supply Voltage
4V
≤
V
IN
≤
14V
Specifications in standard type face are for T
J
= 25˚C and those with
boldface type
apply over
full operating junction temperature range.
V
IN
=10V unless otherwise specified.
Symbol
V
OUT
Parameter
Output Voltage
Conditions
I
LOAD
= 900 mA
Typical
1.8
Limit
1.761/1.719
1.836/1.854
Units
V
V(min)
V(max)
%
%
%
mV
LM2651-1.8 System Parameters
V
OUT
V
OUT
V
OUT
V
HYST
Output Voltage Line
Regulation
Output Voltage Load
Regulation
Output Voltage Load
Regulation
Sleep Mode Output Voltage
Hysteresis
V
IN
= 4V to 14V
I
LOAD
= 900 mA
I
LOAD
= 10 mA to 1.5A
V
IN
= 5V
I
LOAD
= 200 mA to 1.5A
V
IN
= 5V
0.2
1.3
0.3
35
LM2651-2.5 System Parameters
Symbol
V
OUT
Parameter
Output Voltage
Conditions
I
LOAD
= 900 mA
Typical
2.5
Limit
2.43/2.388
2.574/2.575
Units
V
V(min)
V(max)
%
%
%
mV
V
OUT
V
OUT
V
OUT
V
HYST
Output Voltage Line
Regulation
Output Voltage Load
Regulation
Output Voltage Load
Regulation
Sleep Mode Output Voltage
Hysteresis
V
IN
= 4V to 12V
I
LOAD
= 900 mA
I
LOAD
= 10 mA to 1.5A
V
IN
= 5V
I
LOAD
= 200 mA to 1.5A
V
IN
= 5V
0.2
1.3
0.3
48
LM2651-3.3 System Parameters
Symbol
V
OUT
Parameter
Output Voltage
Conditions
I
LOAD
= 900 mA
Typical
3.3
Limit
3.265/3.201
3.379/3.399
Units
V
V(min)
V(max)
%
%
%
mV
V
OUT
V
OUT
V
OUT
V
HYST
Output Voltage Line
Regulation
Output Voltage Load
Regulation
Output Voltage Load
Regulation
Sleep Mode Output Voltage
Hysteresis
V
IN
= 4V to 14V
I
LOAD
= 900 mA
I
LOAD
= 10 mA to 1.5A
V
IN
= 5V
I
LOAD
= 200 mA to 1.5A
V
IN
= 5V
0.2
1.3
0.3
60
3
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LM2651
LM2651-ADJ System Parameters
(V
OUT
= 2.5V unless otherwise specified)
Symbol
V
FB
Parameter
Feedback Voltage
Conditions
I
LOAD
= 900 mA
Typical
1.238
Limit
1.200
1.263
Units
V
V(min)
V(max)
%
%
%
mV
V
OUT
V
OUT
V
OUT
V
HYST
Output Voltage Line
Regulation
Output Voltage Load
Regulation
Output Voltage Load
Regulation
Sleep Mode Output Voltage
Hysteresis
V
IN
= 4V to 14V
I
LOAD
= 900 mA
I
LOAD
= 10 mA to 1.5A
V
IN
= 5V
I
LOAD
= 200 mA to 1.5A
V
IN
= 5V
0.2
1.3
0.3
24
All Output Voltage Versions
Specifications in standard type face are for T
J
= 25˚C and those with
boldface type
apply over
full operating junction tem-
perature range.
V
IN
=10V unless otherwise specified.
Symbol
I
Q
I
QSD
R
SW(ON)
Parameter
Quiescent Current
Quiescent Current in
Shutdown Mode
High-Side or Low-Side Switch
On Resistance (MOSFET On
Resistance + Bonding Wire
Resistance)
MOSFET On Resistance
(High-Side or Low-Side)
Switch Leakage Current - High
Side
Switch Leakage Current - Low
Side
V
BOOT
Bootstrap Regulator Voltage
I
BOOT
= 1 mA
Shutdown Pin Pulled Low
I
SWITCH
= 1A
Conditions
Typical
1.6
7
12/20
110
Limit
2.0
Units
mA
mA(max)
µA
µA(max)
mΩ
R
DS(ON)
I
L
I
SWITCH
= 1A
75
130
130
130
6.75
6.45/6.40
6.95/7.00
mΩ
mΩ(max)
nA
nA
V
V(min)
V(max)
µmho
G
M
V
INUV
V
UV-HYST
I
CL
Error Amplifier
Transconductance
V
IN
Undervoltage Lockout
Threshold Voltage
Hysteresis for the
Undervoltage Lockout
Switch Current Limit
V
IN
= 5V
Rising Edge
1250
3.8
210
2
1.55
2.60
3.95
V
V(max)
mV
A
A(min)
A(max)
mA
V/V
µA
µA(min)
µA
µA(min)
V
V(min)
I
SM
A
V
I
EA_SOURCE
I
EA_SINK
V
EAH
Sleep Mode Threshold Current V
IN
= 5V
Error Amplifier Voltage Gain
Error Amplifier Source Current
Error Amplifier Sink Current
Error Amplifier Output Swing
Upper Limit
100
100
40
25/15
65
30
2.70
2.50/2.40
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4
LM2651
All Output Voltage Versions
Symbol
V
EAL
V
D
f
OSC
Parameter
Error Amplifier Output Swing
Lower Limit
Body Diode Voltage
Oscillator Frequency
(Continued)
Specifications in standard type face are for T
J
= 25˚C and those with
boldface type
apply over
full operating junction tem-
perature range.
V
IN
=10V unless otherwise specified.
Conditions
Typical
1.25
1.35/1.50
I
DIODE
= 1.5A
V
IN
= 4V
1
300
280/255
330/345
D
MAX
I
SS
Maximum Duty Cycle
Soft-Start Current
V
IN
= 4V
Voltage at the SS pin = 1.4V
95
92
11
7
14
I
SHUTDOWN
Shutdown Pin Current
Shutdown Pin Pulled Low
2.2
0.8/0.5
3.7/4.0
v
SHUTDOWN
Shutdown Pin Threshold
Voltage
Thermal Shutdown
Temperature
Thermal Shutdown Hysteresis
Temperature
Falling Edge
0.6
0.3
0.9
165
25
Limit
Units
V
V(max)
V
kHz
kHz(min)
kHz(max)
%
%(min)
µA
µA(min)
µA(max)
µA
µA(min)
µA(max)
V
V(min)
V(max)
˚C
˚C
T
SD
T
SD_HYST
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 maximum allowable power dissipation is calculated by using P
Dmax
= (T
Jmax
− T
A
)/θ
JA
, where T
Jmax
is the maximum junction temperature, T
A
is the
ambient temperature, and
θ
JA
is the junction-to-ambient thermal resistance of the specified package. The 893 mW rating results from using 150˚C, 25˚C, and
140˚C/W for T
Jmax
, T
A
, and
θ
JA
respectively. A
θ
JA
of 140˚C/W represents the worst-case condition of no heat sinking of the 16-pin TSSOP package. Heat sinking
allows the safe dissipation of more power. The Absolute Maximum power dissipation must be derated by 7.14mW per ˚C above 25˚C ambient. The LM2651 actively
limits its junction temperature to about 165˚C.
Note 3:
The human body model is a 100pF capacitor discharged through a 1.5kΩ resistor into each pin.
Note 4:
Typical numbers are at 25˚C and represent the most likely norm.
Note 5:
All limits are guaranteed at room temperature (standard typeface) and at
temperature extremes (boldface type ).
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).
