
Absolute Maximum Ratings (Notes 1, If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
V
IN, EN, POK, BATOK pins: Voltage
0.3V to 5.6V
Junction Temperature (T
J-MAX-ABS)
150C
Continuous Power Dissipation
Internally Limited
V
OUT Short-Circuit to GND Duration
Unlimited
Storage Temperature Range
65C to 150C
Lead Temperature
(Soldering, 5 Sec.)
260C
Human-body model:
Machine model
2kV
200V
Operating Ratings
Input Voltage Range
2.6V to 5.5V
Recommended Output Current
Range
0mA to 120mA
Junction Temperature Range
-40C to 125C
Ambient Temperature Range
-40C to 85C
Thermal Information
Thermal Resistance, MSOP-8
220C/W
Resistance, MSOP-8 Package
(
θ
Electrical Characteristics
Limits in standard typeface and typical values apply for T
J =25
oC. Limits in boldface type apply over the operating junction
temperature range. Unless otherwise specified: 2.6
≤ V
IN
≤ 5.5V, V(EN) = V
IN,C1 =C2 = 1F, CIN =COUT = 10F. (Note 9) Symbol
Parameter
Conditions
Min
Typ
Max
Units
LM2797-1.8, LM2798-1.8, LM2798-2.0
V
OUT
Output Voltage Tolerance
2.8V
≤ V
IN
≤ 4.2V
0mA
≤ I
OUT
≤ 120mA
-5
+5
%of
V
OUT(nom)
4.2V < V
IN
≤ 5.5V
0mA
≤ I
OUT
≤ 120mA
-6
+6
LM2798-1.5
V
OUT
Output Voltage Tolerance
2.8V
≤ V
IN
≤ 4.2V
0mA
≤ I
OUT
≤ 120mA
-6
+6
%of
V
OUT(nom)
4.2V < V
IN
≤ 5.5V
0mA
≤ I
OUT
≤ 120mA
-6
+6
All Output Voltage Options
I
Q
Operating Supply Current
I
OUT = 0mA
35
50
A
I
SD
Shutdown Supply Current
V(EN) = 0V
0.1
2
A
V
R
Output Voltage Ripple
LM2798-1.8: V
IN = 3.6V, IOUT = 120mA
20
mV
p-p
E
PEAK
Peak Efficiency
LM2798-1.8: V
IN = 3.0V, IOUT = 60mA
90
%
E
AVG
Average Efficiency over
Li-Ion Input Voltage Range
LM2798-1.5: 3.0
≤ V
IN
≤ 4.2V, I
OUT = 60mA
76
%
LM2798-1.8: 3.0
≤ V
IN
≤ 4.2V, I
OUT = 60mA
82
LM2798-2.0: 3.0
≤ V
IN
≤ 4.2V, I
OUT = 60mA
75
t
ON
Turn-On Time
LM2798, V
400
s
LM2797, V
100
f
SW
Switching Frequency
500
kHz
I
SC
Short-Circuit Current
V
IN = 3.6, VOUT =0V
25
mA
Enable Pin (EN) Characteristics
V
IH
EN pin Logic-High Input
0.9
V
IN
V
IL
EN pin Logic-Low Input
0
0.4
V
I
EN
EN pin input current
V
EN =0V
0
nA
V
EN = 5.5V
30
LM2797/LM2798
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