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TSZ02201-0J4J0AJ00580-1-2

© 2013 ROHM Co., Ltd. All rights reserved.

21.Feb.2014 Rev.002

www.rohm.com

TSZ22111

• 15 • 001

BD9161FVM-LB

Description of Block - continued

・100% Duty control

Max duty is 100%. (@ Pch MOS FET always ON) In usual PWM control, in case output voltage cannot keep (ex, drop

of input voltage), oscillation frequency becomes lower and finally it becomes 100% duty. The output voltage is a value

that depends only by on a voltage hang from the input voltage to Pch MOS FET, and can keep the output voltage even

with the low input voltage.

Figure 6. Diagram of current mode PWM control

Figure 7. PWM switching timing chart

Figure 8. SLLM

Current

Comp

SET

RESET

SW

GND

GND

GND

SENSE

FB

Current

Comp

SET

RESET

SW

GND

GND

GND

0A

SENSE

FB

Not switching

OSC

Level

Shift

Driver

Logic

R Q

S

SW

ITH

Current

Comp

Gm Amp.

SET

RESET

FB

Load

SENSE