Datasheet

Datasheet
Datasheet
25/34
BD9271KUT
TSZ02201-0F1F0C100260-1-2
© 2013 ROHM Co., Ltd. All rights reserved.
27.Feb.2015 Rev.004
www.rohm.com
TSZ22111・15・001
◆Condition for protections
Protection
name
Protection pin Detection Condition Release Condition Protection Type
LED OPEN
Dx
Dx < 0.1V
CHx=EN,PWMx=High
Dx > 0.1V
Abnormal detection
ERR_DET signal output
LEDSHORT
Dx
Dx > 5V
(LSP=OPEN)
CHx=EN,PWMx=High
Dx < 5V
(LSP=OPEN)
Abnormal detection
ERR_DET signal output
RES SHORT
Sx
Sx < 0.15V(*1)
CHx=EN,PWMx=High
Sx > 0.15V(*1)
Abnormal detection
ERR_DET signal output
MOSSHORT
Sx
Sx>0.15V(*1)
CHx=EN,PWMx=Low
Sx < 0.15V(*1)
Abnormal detection
ERR_DET signal output
VCC UVLO
VCC VCC<6.7V VCC>7.0V
Abnormal detection
ERR_DET signal output
(*1)…The initial value of the detect threshold of RESSHORT and MOSSHORT are 0.15V. And those correspond to the
register LEDREF.
・LED_OPEN protection
When PWMx=HIGH, If Drain pin becomes 0.1V(typ) or lower, ERR_DET = LOW is outputted and LED OPEN error will be
detected.
① When PWMx=HIGH, LED OPEN error is detected. ERR_DET=LOW is outputted.
If drain pin voltage is release condition, ERR_DET=HIGH is outputted.
② When PWMx=LOW, LED OPEN error is not detected.
③ When PWMx=HIGH, LED OPEN error is detected. When PWMx=LOW, If drain pin voltage is release condition,
ERR_DET output keep-hold.
・LED_SHORT protection
When PWMx=HIGH, If Drain pin becomes 5V(typ) or more (LSP=OPEN), ERR_DET = LOW is outputted and LED SHORT
error will be detected.
① When PWMx=HIGH, LED SHORT error is detected. ERR_DET=LOW is outputted.
If drain pin voltage is released, ERR_DET=HIGH is outputted.
② When PWMx=LOW, LED SHORT error is not detected.
③ When PWMx=HIGH, LED SHORT error is detected. When PWMx=LOW, even though the drain pin voltage is
realeased, ERR_DET output is kept.
Figure 23. LED OPEN Protection
Figure 24. LED SHORT Protection
(internal)
(internal)