BD6067GU_11 ROHM [Rohm], BD6067GU_11 Datasheet - Page 20

• Manufacturer Part Number: BD6067GU_11
• Description: White Backlight LED Drivers for Small to Medium LCD Panels (Switching Regulator Type)
• Manufacturer: ROHM [Rohm]

© 2011 ROHM Co., Ltd. All rights reserved.
BD6067GU, BD6069GUT, BD6071HFN, BD6072HFN
►BD6069GUT, BD6072HFN
●Block diagram, recommended circuit example, pin location diagram
●Pin assignment table
●Operation
www.rohm.com
BD6069GUT is a fixed frequency PWM current mode DC/DC converter, and adopts synchronous rectification architecture.
As for the inputs of the PWM comparator as the feature of the PWM current mode, one is overlapped with error components
from the error amplifier, and the other is overlapped with a current sense signal that controls the inductor current into Slope
waveform for sub harmonic oscillation prevention. This output controls Q1 and Q2 via the RS latch.
Timing of Q1 and Q2 is precisely adjusted so that they will not turn ON at the same time, thus putting them into
non-overlapped relation. In the period where Q1 is ON, energy is accumulated in the external inductor, and in the period
where Q1 is OFF, energy is transferred to the capacitor of VOUT via Q2. Further, BD6069GUT/BD6072HFN has many safety
functions, and their detection signals stop switching operation at once.
PIN Name
GNDA
VOUT
TEST
GND
VFB
VIN
SW
EN
Fig.63 Pin location diagram VCSP60N1 (Bottom view)
In/Out
Out
In
In
In
In
In
-
-
1µF
C
C1
B1
A1
<BD6069GUT>
IN
BD6069GUT
VIN
Q1
C2
A2
C1
C2
A1
A2
A3
B1
B3
C3
Fig.62 Block diagram and recommended circuit diagram
GND
SW
22µH
L
C3
B3
A3
Ball number
Q2
GNDA
Q
Q
Current
Sence
BD6072HFN
S
R
300kΩ
8
1
2
3
4
7
6
5
20/29
TSD
Control
EN
Analog GND
Enable control (pull down is integrated on resistance)
TEST input (pull down is integrated on resistance)
Power supply input
Feedback input voltage
Output
Switching terminal
Power GND
TEST
Fig.64 Pin location diagram HSON8 (Top view)
PWMcomp
over voltage
short protect
protect
+
-
OSC
+
ERRAMP
<BD6072HFN>
1
8
+
-
+
-
-
+
7
2
Function
6
3
V
VOUT
FB
5
4
C
1µF
OUT
2011.01 - Rev.C
Technical Note
24Ω
R
FB
white LED