LM2640MTC-ADJ National Semiconductor, LM2640MTC-ADJ Datasheet - Page 7

• Manufacturer Part Number: LM2640MTC-ADJ
• Description: Dual Adjustable Step-Down Switching Power Supply Controller
• Manufacturer: National Semiconductor

I
I
Voltage References and Linear Voltage Regulator
V
V
V
V
Logic Inputs
V
V
V
COMP1
COMP1
BG
REF
LIN
UVLO
IH
IH
IL
Electrical Characteristics
Typicals and limits appearing in regular type apply for T
tion temperature range for operation, 0 to +125˚C. Unless otherwise specified under the Parameter or Conditions columns, V
Note 1: Unless otherwise specified, all voltages are with respect to the voltage at the GND and PGND pins.
Note 2: Absolute Maximum Ratings are 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 3: The Absolute Maximum power dissipation depends on the ambient temperature. The 883 mW rating results from substituting 150˚C, 70˚C, and 90.6˚C/W
for T
junction temperature, T
worst-case condition of no heat sinking of the 28-pin TSSOP. Heat sinking allows the safe dissipation of more power. The Absolute Maximum power dissipation must
be derated by 11.04 mW per ˚C above 70˚C ambient. The LM2640 actively limits its junction temperature to about 150˚C.
Note 4: For detailed information on soldering plastic small-outline packages, refer to the Packaging Databook available from National Semiconductor Corporation.
Note 5: For testing purposes, ESD was applied using the human-body model, a 100 pF capacitor discharged through a 1.5 k
Note 6: A typical is the center of characterization data taken with T
Note 7: All limits are guaranteed. All electrical characteristics having room-temperature limits are tested during production with T
guaranteed by correlating the electrical characteristics to process and temperature variations and applying statistical process control.
= 10V, and V
Symbol
Jmax
, I
, I
COMP2
COMP2
, T
A
, and
SD
JA
COMP Output Source Current V
COMP Output Sink Current
Bandgap Voltage
Reference Voltage
Output Voltage of the Linear
Voltage Regulator
Undervoltage Lockout
Threshold
LIN-to-V
Threshold
Minimum High Level Input
Voltage (SD, ON/OFF1,
ON/OFF2, and SYNC)
Minimum High Level Input
Voltage (2NDFB/FPWM)
Maximum Low Level Input
Voltage (SD, ON/OFF1,
ON/OFF2, SYNC, and
2NDFB/FPWM)
Maximum Input Leakage
Current (SD, ON/OFF1,
ON/OFF2, and SYNC)
= V
respectively into the formula P
A
is the ambient temperature, and
ON/OFF1
OUT
Parameter
= V
Switch-Over
ON/OFF2
max
= 5V. (Note 2), (Note 6) and (Note 7)
= (T
(Continued)
Jmax
JA
V
V
V
0.01 mA
V
0.01 mA
V
−40˚C
6V
0 mA
(Note 11)
(Note 11)
−40˚C
V
−40˚C
Logic Input Voltage 0 or 5V
is the junction-to-ambient thermal resistance of the package. A
FB1
COMP2
FB1
COMP2
LIN
LIN
OUT
- T
A
A
)/
V
= V
= V
taken at CSL1
= T
6V
6V
IN
J
JA
I
= 1V
= 0.2V
LIN
, where P
J
= 25˚C. Limits appearing in boldface type apply over the entire junc-
T
T
T
FB2
FB2
= 25˚C. Typicals are not guaranteed.
J
J
J
I
I
30V,
REF
REF
Conditions
= 1V, V
= 1.4V, V
+125˚C
+125˚C
+125˚C
25 mA
7
max
5 mA Source,
5 mA Source,
is the Absolute Maximum power dissipation, T
COMP1
COMP1
=
=
Typical
1.238
±
2.5
2.5
4.0
4.0
4.8
90
60
0.1
5
A
resistor.
= 25˚C. All hot and cold limits are
JA
2.555
Jmax
Limit
2.45
2.55
2.45
4.42
2.45
4.6
5.4
3.6
4.4
3.6
2.4
2.6
0.8
of 90.6˚C/W represents the
40
40
is the Absolute Maximum
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µA(min)
µA(min)
V(max)
V(max)
V(max)
V(max)
V(max)
V(max)
V(min)
V(min)
V(min)
V(min)
V(min)
V(min)
V(min)
V(min)
Units
µA
µA
µA
V
V
V
V
V
IN