BD9845FV-E2 Rohm Semiconductor, BD9845FV-E2 Datasheet - Page 13

• Manufacturer Part Number: BD9845FV-E2
• Description: IC REG SW STEP DOWN 1CH 14-SSOP
• Manufacturer: Rohm Semiconductor
• Type: Step-Down (Buck)r

Specifications of BD9845FV-E2

• Internal Switch(s): No
• Synchronous Rectifier: No
• Number Of Outputs: 1
• Current - Output: 1A
• Frequency - Switching: 100kHz ~ 1.5MHz
• Voltage - Input: 3.6 ~ 35 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 14-SSOP
• Power - Output: 500mW
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Output: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: BD9845FV-E2TR

●I/O equivalent circuit diagram
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BD9845FV
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5) About board layout
6) PIN processing of channel unused
CT
When only one channel is used, process unused channels as shown above.
In order to make full use of IC performance, fully investigate the items below in addition to general precautions.
STB
・ Each output of OCP+/OCP- is such a sensitive circuit. When wiring is routed around, it is easily subjected to noise.
・ Switching of large current is likely to generate noise. Try to make the large current route (VIN, Rsense, FET, L, Di,
・ C
・ Also be careful not to allow common impedance to sense family GND.
VREF
VCC
Try to make the wiring as short as possible.
and Cout) as thick and short as possible, and try to apply one-point grounding for GND. OUT terminal is also a
switching line, and it must be wired along a distance as short as possible. (When multi-layer board is used, shielding
by intermediate layer also seems to be effective.)
protected against external influence.
4pin (STB)
CT
VREF
VCC
INV
and C
12pin (INV)
VCC
5pin (C5V)
VREF
VREF
VREF DT
2pin(CT)
VREF
1
VREF
VREF
14
VCC
VREF
are reference of all, and must be wired along the shortest distance to GND of IC stabilized to be
SS INV
13
VREF
VREF
12
VCC
Fig.43
FB
11
C5V
SEL
OCP- OCP+ VCC OUT
10pin (SEL)
9
VCC
VCC VCC
8
DT
7
6
VREF
13/15
6pin (OUT)
14pin (DT)
11pin (FB)
VREF
VCC
C5V
VCC
C5V
VREF
VREF
OUT
1pin (VREF)
FB
VCC
VCC
VREF
SS
VREF
OCP-
OCP+
3pin (GND) , 7pin (VCC)
8pin (OCP+)
9pin (OCP-)
13pin (SS)
VCC
C5V
2009.05 - Rev.A
Technical Note
VCC
C5V
GND
VREF
VCC
VREF
VCC
C5V
VCC
C5V
VCC