BD9B301MUV-LB Datasheet, PDF (2/33 Pages) Rohm – Over Current Protection

BD9B301MUV-LB
Pin Configuration
(TOP VIEW)
Datasheet
Pin Descriptions
Pin No.
1, 2
3, 4
5
6
7
8
9
10, 11, 12
13
14
15
16
-
Figure 2. Pin Assignment
Pin Name
PVIN
PGND
AGND
FB
FREQ
MODE
SS
SW
BOOT
PGD
EN
AVIN
E-Pad
Function
Power supply terminals for the switching regulator.
These terminals supply power to the output stage of the switching regulator.
Connecting a 10µF ceramic capacitor is recommended.
Ground terminals for the output stage of the switching regulator.
Ground terminal for the control circuit.
An inverting input node for the error amplifier and main comparator.
See page 22 for how to calculate the resistance of the output voltage setting.
Terminal for setting switching frequency. Connecting this terminal to ground makes
switching to operate constant on-time corresponding to 2.0MHz. Connecting this
terminal to AVIN makes switching to operate constant on-time corresponding to
1.0MHz. Please fix this terminal to AVIN or ground in operation.
Terminal for setting switching control mode. Connecting this terminal to AVIN forces
the device to operate in the fixed frequency PWM mode. Connecting this terminal to
ground enables the Deep-SLLM control and the mode is automatically switched
between the Deep-SLLM control and fixed frequency PWM mode. Please fix this
terminal to AVIN or ground in operation.
Terminal for setting the soft start time. The rise time of the output voltage can be
specified by connecting a capacitor to this terminal. See page 23 for how to calculate
the capacitance.
Switch nodes. These terminals are connected to the source of the High-Side
MOSFET and drain of the Low-Side MOSFET. Connect a bootstrap capacitor of 0.1
µF between these terminals and BOOT terminal. In addition, connect an inductor of
0.47µH to 1µH (FREQ=L), 1μH to 1.5μH (FREQ=H) considering the direct current
superimposition characteristic.
Terminal for bootstrap. Connect a bootstrap capacitor of 0.1 µF between this terminal
and SW terminals. The voltage of this capacitor is the gate drive voltage of the
High-Side MOSFET.
A “Power Good” terminal, an open drain output. Use of pull up resistor is needed. See
page 17 for how to specify the resistance. When the FB terminal voltage reaches
more than 80% of 0.8 V, the internal Nch MOSFET turns off and the output turns High.
Enable terminal. Turning this terminal signal Low (0.8V or lower) forces the device to
enter the shutdown mode. Turning this terminal signal High (2.0V or higher) enables
the device. This terminal must be terminated.
Terminal for supplying power to the control circuit of the switching regulator.
Connecting a 0.1µF ceramic capacitor is recommended.
A backside heat dissipation exposed pad. Connecting to the internal PCB ground
plane by using multiple vias provides excellent heat dissipation characteristics.
www.rohm.com
© 2015 ROHM Co., Ltd. All rights reserved.
TSZ22111 • 15 • 001
2/30
TSZ02201-0J3J0AJ00830-1-2
2015.04.02 Rev.001