lm5025asdx National Semiconductor Corporation, lm5025asdx Datasheet - Page 2

• Manufacturer Part Number: lm5025asdx
• Description: Active Clamp Voltage Mode Pwm Controller
• Manufacturer: National Semiconductor Corporation

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Connection Diagram
Ordering Information
Pin Description
PIN
Order Number
LM5025AMTC
LM5025AMTCX
LM5025ASD
LM5025ASDX
1
2
3
4
5
6
7
NAME
RAMP
TIME
REF
CS1
CS2
V
V
CC
IN
Source Input Voltage
Modulator ramp signal
Current sense input for cycle-by-cycle limiting If CS1 exceeds 0.5V the outputs will go into
Current sense input for soft restart
Output overlap/Deadtime control
Precision 5 volt reference output
Output from the internal high voltage start-up
regulator. The V
7.6V.
Package Type
TSSOP-16
TSSOP-16
LLP-16
LLP-16
DESCRIPTION
CC
voltage is regulated to
16-Lead TSSOP, LLP
NSC Package Drawing
MTC-16
MTC-16
SDA-16A
SDA-16A
2
Input to start-up regulator. Input range 13V to 90V,
with transient capability to 105V.
An external RC circuit from Vin sets the ramp slope.
This pin is discharged at the conclusion of every
cycle by an internal FET, initiated by either the
internal clock or the V*Sec Clamp comparator.
Cycle-by-Cycle current limit. CS1 is held low for
50ns after OUT_A switches high providing leading
edge blanking.
If CS2 exceeds 0.5V the outputs will be disabled and
a softstart commenced. The soft-start capacitor will
be fully discharged and then released with a pull-up
current of 1µA. After the first output pulse (when SS
=1V), the SS charge current will revert back to 20µA.
An external resistor (R
time or dead time for the active clamp output. An
R
produces in-phase OUT_A and OUT_B pulses with
overlap. An R
and REF produces out-of-phase OUT_A and OUT_B
pulses with deadtime.
Maximum output current: 10mA Locally decouple
with a 0.1µF capacitor. Reference stays low until the
V
If an auxiliary winding raises the voltage on this pin
above the regulation setpoint, the internal start-up
regulator will shutdown, reducing the IC power
dissipation.
CC
SET
UV comparator is satisfied.
20107416
resistor connected between TIME and GND
APPLICATION INFORMATION
SET
resistor connected between TIME
Supplied As
92 Units per anti-static tube
2500 Units on Tape and Reel
Available Soon
Available Soon
SET
) sets either the overlap