Datasheet

Datasheet

6/36

BD81A24MUV-M/EFV-M

TSZ02201-0T3T0C600070-1-2

© 2016 ROHM Co., Ltd. All rights reserved.

2016.10.19 Rev.003

www.rohm.com

TSZ22111・15・001

4. Protect Function

Table 2. The detect condition of each protect function and the operation during detection

Protect Function

Detect Condition

Operation During Detection

[Detection]

[Release/ Cancellation]

UVLO

VCC >4.0V and VREG>3.5V

All Blocks Shuts down

(Except for VREG)

TSD

Tj>175°C

Tj<150°C

All Blocks Shuts down

(Except for VREG)

OVP

DCDC switching OFF

OCP

DCDC switching OFF

SCP

One of the LED1-4

is under 0.3V

or

VOVP<0.57V

(100ms delay @300kHz)

EN Reset

or

UVLO Reset

After SCP delay time,

all block Latch Off

(Except for VREG)

LED Open Protection

VLED<0.3V

and VOVP>2.0V

EN Reset

or

UVLO Reset

Only the detected channel latches

OFF

LED Short Protection

VLED>4.5V

(100ms delay @300kHz)

EN Reset

or

UVLO Reset

After LED Short delay time,

only the detected channel latch OFF

Figure 9. Protection Flag Output Block Diagram

The operating status of the protection is propagated to FAIL1 and FAIL2 terminals (open-drain outputs). FAIL1 becomes low

when OVP or OCP protection is detected, whereas FAIL2 becomes low when SCP, LED open or LED short is detected. If

the FAIL terminal will not be used as flag output, please make the FAIL terminal open or connect it to GND. But if the FAIL

terminal will be used as a flag output, it is recommended to pull-up the FAIL1, 2 terminals to VREG terminal. The

recommended value of pull-up resistance is 100kΩ.