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BD91361MUV

Datasheet

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© 2012 ROHM Co., Ltd. All rights reserved.

TSZ22111･15･001

TSZ02201-0J3J0AJ00200-1-2

06.Oct.2014 Rev.002

2. Description of Functions

(1) Soft-Start Function

During start-up, the soft-start circuit gradually establishes the output voltage to limit the input current. This prevents

the overshoot in the output voltage and inrush current.

(2) Shutdown Function

When EN terminal is set

to “Low”, the device operates in Standby Mode, and all the functional blocks such as

reference voltage circuit, internal oscillator and drivers are turned to OFF. Circuit current during standby is 0µA

(Typ).

(3) UVLO Function

This circuit detects whether the supplied input voltage is sufficient to provide the output voltage of this IC.

A hysteresis width of 50mV (Typ) is provided to prevent the output from chattering.

Figure 24. Soft-Start, Shutdown, UVLO Timing Chart

(4) Short-Circuit Protection with Time Delay Function

To protect the IC from breakdown, the short-circuit turns the output OFF when the internal current limiter is

restarting EN or by resetting UVLO.

Figure 25. Short-Circuit Protection with Time Delay Diagram

Hysteresis 50mV

Soft start

Standby Mode

Operating Mode

Standby

Mode

Operating Mode

Standby

Mode

Operating Mode

Standby Mode

UVLO

EN

UVLO

UVLO

EN

1msec

Output voltage OFF Latch

Output Current in non-control

Output Current in control by limit value

(With fall of the output voltage, limit value goes down)

EN

Timer Latch

EN

Standby Mode

Operated Mode

Standby Mode

Operated Mode

EN

Limit

Until output voltage goes up the half of

(No timer latch, only limit to the output current)