Connection Diagram

20147902

16-Lead TSSOP, LLP

Ordering Information

Order Number

Package Type

NSC Package Drawing

Supplied As

LM5026MT

TSSOP-16

MTC16

92 Units per anti-static tube

LM5026MTX

TSSOP-16

MTC16

2500 Units on Tape and Reel

LM5026SD

LLP-16

SDA16A

Available Soon

LM5026SDX

LLP-16

SDA16A

Available Soon

Pin Descriptions

PIN

NAME

DESCRIPTION

APPLICATION INFORMATION

1

VIN

Input Voltage Source

Input to the Start-up Regulator. Operating input range is 13V to 100V

with transient capability to 105V. For power sources outside of this

range, the LM5026 can be biased directly at VCC by an external

regulator.

2

UVLO

Line Under-Voltage Lockout An external voltage divider from the power source sets the shutdown

and standby comparator levels. When UVLO reaches the 0.4V threshold

the VCC and REF regulators are enabled. At the 1.25V threshold the SS

pin is released and the device enters the active mode.

3

CS

Current Sense input for

current mode control and

current limit

If CS exceeds 0.5V the output pulse will be terminated, entering

cycle-by-cycle current limit. An internal switch holds CS low for 100nS

after OUT_A switches high to blank leading edge transients.

4

RES

Restart Timer

If cycle-by-cycle current limit is reached during any cycle, a 10uA current

is sourced to the RES pin capacitor. If the RES capacitor voltage

reaches 2.5V, the soft-start capacitor will be fully discharged and then

released with a pull-up current of 1uA. After the first output pulse at

OUT_A (when SS =1.4V), the SS pin charging current will revert back to

50 µA.

5

TIME

Gate Drive Overlap or

Deadtime Control

An external resistor (RSET) sets either the overlap time or deadtime for

the active clamp output. An RSET resistor connected between TIME and

AGND produces in-phase OUT_A and OUT_B pulses with overlap. An

RSET resistor connected between TIME and REF produces out-of-phase

OUT_A and OUT_B pulses with deadtime.

6

REF

Output of 5V Reference

Maximum output current is 10mA. Locally decouple with a 0.1µF

capacitor.

7

VCC

Output of the high voltage

start-up regulator. The VCC

voltage is regulated to 7.6

V.

If an auxiliary winding raises the voltage on this pin above the regulation

setpoint, the internal start-up regulator will shutdown, thus reducing the

IC power dissipation.

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2