BD9324EFJ-E2 Rohm Semiconductor, BD9324EFJ-E2 Datasheet - Page 8

• Manufacturer Part Number: BD9324EFJ-E2
• Description: IC CONVERTER REG 4A HTSOP-J8
• Manufacturer: Rohm Semiconductor
• Series: -r
• Type: Step-Down (Buck), PWM - Current Moder

Specifications of BD9324EFJ-E2

• Internal Switch(s): Yes
• Synchronous Rectifier: Yes
• Number Of Outputs: 1
• Voltage - Output: 1 V ~ 18 V
• Current - Output: 4A
• Frequency - Switching: 380kHz
• Voltage - Input: 4.75 V ~ 18 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: *
• Package / Case: *
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

z Selecting Application Components
(1) Output LC constant (Buck Converter)
IL
The inductance L to use for output is decided by the rated current I
inductance.
Set with sufficient margin because the inductance L value may have the dispersion of ± 30%.
For the capacitor C to use for the output, select the capacitor which has the larger value in the ripple voltage V
value and the drop voltage permissible value at the time of sudden load change.
Perform setting so that the voltage is within the permissible ripple voltage range.
For the drop voltage V
However, 10μs is the rough calculation value of the DC/DC response speed.
Make Co settings so that these two values will be within the limit values.
Adjust so that I
equation.
Output ripple voltage is decided by the following equation.
¨V
V
PP
¨I
DR
L
=
=
=
Fig.
OMAX
1
L
DR
Co
¨I
¨I
during sudden load change, please perform the rough calculation by the following equation.
L
u (Vcc - Vo) u
u R
+ ¨I
ESR +
u 10 us
L
does not reach the rated current value I
2Co
¨I
I
L
OMAX
[V]
Vcc
reach the rated
value level
Vo
u
+
Vcc
'I
u
Vo
L
I
current
OMAX
8/14
should not
t
1
f
u
ILR
[A]
mean
1
f
LR
and input current maximum value I
[V]
LR
. At this time, ¨I
VCC
L
can be obtained by the following
I
L
Fig.
L
Co
OMAX
Vo
PP
of the
permissible