OVP-

LOW SIDE ON

UVP

PRE-BIASED

STARTUP CONDITION

CURRENT LIMIT

CURRENT LIMIT

DISABLE

0.8V

2.7V

Soft Start Time

`

0.8V

0.0V

`

LM20136

www.ti.com

SNVS564B – JANUARY 2009 – REVISED APRIL 2013

Figure 28. Powergood Behavior

UVLO

The LM20136 has a built-in under-voltage lockout protection circuit that keeps the device from switching until the

input voltage reaches 2.7V (typical). The UVLO threshold has 45 mV of hysteresis that keeps the device from

responding to power-on glitches during start up. If desired the turn-on point of the supply can be changed by

design guide.

Thermal Protection

Internal thermal shutdown circuitry is provided to protect the integrated circuit in the event that the maximum

junction temperature is exceeded. When activated, typically at 160°C, the LM20136 tri-states the power FETs

and resets soft start. After the junction cools to approximately 150°C, the part starts up using the normal start up

routine. This feature is provided to prevent catastrophic failures from accidental device overheating.

Copyright © 2009–2013, Texas Instruments Incorporated

Submit Documentation Feedback

13

Product Folder Links: LM20136