lm2637mx National Semiconductor Corporation, lm2637mx Datasheet - Page 2

• Manufacturer Part Number: lm2637mx
• Description: Motherboard Power Supply Solution With A 5-bit Programmable Switching Controller And Two Linear Regulator Controllers
• Manufacturer: National Semiconductor Corporation

www.national.com
I
I
I
I
SWITCHING SECTION
V
I
f
D
D
R
R
R
V
V
V
V
t
t
V
V
V
I
V
I
GA
EN
VID
CC
Q_VCC
Q_VDD
OSC
PWGD
PWBAD
CS+
OVP
DACOUT
CC_TH1
CC_TH2
DAC_IH
DAC_IL
PWGD_HI
PWGD_LO
OVP_TRP
OCP
MAX
MIN
SNS1
DS_SRC
DS_SINK
Absolute Maximum Ratings
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Electrical Characteristics
V
appearing in boldface type apply over the 0˚C to +70˚C range.
Symbol
V
V
Junction Temperature
Power Dissipation (Note 2)
CC
CC
DD
= 5V, V
EN Pin internal Pull-Up Current
VID Pins internal Pull-Up Current
Operating V
V
5-Bit DAC Output Voltage
V
Oscillator Frequency
Maximum Duty Cycle
Minimum Duty Cycle
SNS1 Pin Resistance to Ground
Gate Driver Resistance When
Sourcing Current
Gate Driver Resistance When
Sinking Current
Rising V
Power-On Reset
Falling V
Power-On Reset
DAC Input High Voltage
DAC Input Low Voltage
PWGD Response Time
PWGD Response Time
PWGD High Trip Point
PWGD Low Trip Point
OVP Pin Trip Point
CS+ Pin Sink Current
Over-Current Trip Point (CS+
and CS− Differential Voltage)
OVP Pin Source Current
Error Amplifier DC Gain
DD
CC
DD
= 12V unless otherwise specified. Typicals and limits appearing in plain type apply for T
Shutdown Current
Shutdown Current
CC
CC
Parameter
Threshold for
CC
Threshold for
Current
(Note 1)
EN = 5V, VID = 10111
EN = 0V, VID Pins Floating
(Note 3)
EN = 0V, VID Pins Floating
RT = 100 kΩ
RT = 25 kΩ
SNS1 Rises from 0V to Rated
Output Voltage
SNS1 Falls from Rated Output
Voltage to 0V
% Above Rated Output Voltage
when output Voltage
% Above Rated Output Voltage
when output Voltage↓ (Note 4)
% Below Rated Output Voltage
when output Voltage
% Below Rated Output Voltage
when output Voltage↓ (Note 4)
% SNS1 Above Rated Output
CS+ = 5V
CS+ = 2V, CS− Drops from 2V
OVP = 3V
150˚C
1.6W
17V
7V
Conditions
2
Operating Ratings
Storage Temperature
ESD Susceptibility
Soldering Time, Temperature (10 sec.)
V
Junction Temperature Range
↑
↑
CC
N−1.5%
Min
204
126
8.5
3.0
3.5
60
60
15
41
10
2
2
5
6
1000
11.5
Typ
245
185
1.5
1.5
3.6
8.4
3.4
2.6
9.5
90
90
95
10
18
55
76
(Note 1)
N
6
4
0
6
4
7
A
= T
N+1.5%
−65˚C to +150˚C
J
Max
140
140
286
244
7.5
4.3
1.3
13
15
10
13
13
21
69
4.75V to 5.25V
= +25˚C. Limits
3
9
6
0˚C to +125˚C
2.5 kV
300˚C
Units
kHz
mA
mA
mV
mA
µA
µA
µA
kΩ
µA
dB
µs
µs
%
%
%
%
%
Ω
Ω
V
V
V
V
V