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BD8962MUV

Datasheet

TSZ02201-0J3J0AJ00030-1-2

02.Oct.2014 Rev.002

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

www.rohm.com

TSZ22111・15・001

2. Description of Operations

(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 the EN terminal is shifted

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

including the reference voltage circuit, internal oscillator and drivers are turned OFF. Circuit current during standby is

0µA (Typ).

(3) UVLO Function

The UVLO circuit detects whether the input voltage is sufficient to obtain the output voltage of this IC. A hysteresis

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

Figure 20. Soft Start, Shutdown, UVLO Timing Chart

(4) Short Circuit Protection with Time Delay Function

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

restarting EN or by resetting UVLO.

Figure 21. Short Current Protection Circuit with Time Delay Timing Chart

Hysteresis 50mV

tss

tss

tss

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 controlled by limit value

(Limit value changes in proportion to output voltage)

EN

Timer Latch

EN

Standby Mode

Operated Mode

Standby Mode

Operated Mode

EN

Limit

Until output voltage goes up to half of Vo or over,

timer latch is not operated.

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