BD8966FVM-TR Rohm Semiconductor, BD8966FVM-TR Datasheet - Page 6

• Manufacturer Part Number: BD8966FVM-TR
• Description: IC SWITCHING REG W/MOSFET MSOP8
• Manufacturer: Rohm Semiconductor
• Series: -r
• Type: Step-Down (Buck), PWM - Current Moder

Specifications of BD8966FVM-TR

• Internal Switch(s): Yes
• Synchronous Rectifier: Yes
• Number Of Outputs: 1
• Voltage - Output: 1 V ~ 2.5 V
• Current - Output: 800mA
• Frequency - Switching: 1MHz
• Voltage - Input: 4 V ~ 5.5 V
• Operating Temperature: -25°C ~ 85°C
• Mounting Type: *
• Package / Case: *
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

●Operation
© 2010 ROHM Co., Ltd. All rights reserved.
BD8966FVM
www.rohm.com
BD8966FVM is a synchronous rectifying step-down switching regulator that achieves faster transient response by employing
current mode PWM control system.
○Synchronous rectifier
○Current mode PWM control
It does not require the power to be dissipated by a rectifier externally connected to a conventional DC/DC converter IC,
and its P.N junction shoot-through protection circuit limits the shoot-through current during operation, by which the power
dissipation of the set is reduced.
Synthesizes a PWM control signal with a inductor current feedback loop added to the voltage feedback.
・PWM (Pulse Width Modulation) control
The oscillation frequency for PWM is 1 MHz. SET signal form OSC turns ON a P-channel MOS FET (while a
N-channel MOS FET is turned OFF), and an inductor current I
receives two signals, a current feedback control signal (SENSE: Voltage converted from I
control signal (FB), and issues a RESET signal if both input signals are identical to each other, and turns OFF the
P-channel MOS FET (while a N-channel MOS FET is turned ON) for the rest of the fixed period. The PWM control
repeats this operation.
V
OUT
Current
RESET
Gm Amp.
Comp
V
SET
SW
OUT
I
L
Level
Shift
Fig.20 Diagram of current mode PWM control
ITH
FB
SENSE
Current
Comp
Fig.21 PWM switching timing chart
RESET
OSC
SET
R Q
S
6/14
Driver
Logic
L
increases. The current comparator (Current Comp)
SW
PV
GND
GND
GND
I
V
L
I
(AVE)
OUT
L
CC
(AVE)
FB
SENSE
Load
L
) and a voltage feedback
V
OUT
Technical Note
2010.04 - Rev.B