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ROHM Semiconductor |
Datasheet
PWM Control Type
DC/DC Converter IC for AC/DC Driver
BD7672BG
●General Description
BD7672BG is a PWM controller type DC/DC converter
for AC/DC that provides an optimum system for all
products that requires an electrical outlet. This product
supports both isolated and non-isolated devices. IC
enables simple design of low-power electrical
converters. With switching MOSFET and current
detection resistor as external devices, it enables more
freedom in design.
Since the peak current control is utilized, peak current
is controlled in each cycle, application excels wide
bandwidth and transient response.
BD7672BG includes various protective functions such
as soft start function, burst function, per-cycle over
current limiter, VCC overvoltage protection and
overload protection.
An external latch pin (COMP pin) is provided, so that
latch stopping (OFF) can be set by external signals.
This function is available as overheating protection and
over output voltage protection.
The PWM switching frequency is fixed at 65 kHz.
A frequency hopping function is included which contributes
to low EMI.
●Key Specifications
Power Supply Voltage range:
8.5V to 25.0V
Operating Current:
Normal: 0.60mA (Typ)
Burst: 0.40mA (Typ)
Oscillation Frequency:
65kHz (Typ)
Operating Temperature range:
-40°C to +85°C
●Package
SSOP6
W(Typ) x D (Typ) x H (Max)
2.90mm x 2.80mm x1.25mm
●Features
■ PWM frequency of 65kHz
■ PWM current mode method
■ Low circuit current when UVLO is ON
(12μA at VCC=12V)
■ Low circuit current without load
(Burst operation when load is light)
■ Built-in SW frequency hopping function
■ 250nsec leading-edge blanking
■ VCC UVLO / OVP
■ Per-cycle over current protection circuit
■ Soft start
■ Output overload protection (Self-restart protection)
■ External latch function for COMP pin
(Over heating protection function)
●Applications
AC adapters and household appliances (vacuum cleaners,
humidifiers, air cleaners, air conditioners, refrigerators, IH
cooking heaters, rice cookers, etc.)
●Typical Application Circuit
F1
ZNR1
FL1
C8
C9
F2
D1 R1
+ C1
Q1
R5
76767732B
C2 R2
D2
R4 D3
+
C3
ZD
C4 R3
R11
D4
+ C5
R6
C7
U1 R7
R9
C6 R8
U2
R10
Figure 1, Application Diagram (12 V 1A Isolated Type)
○Product structure:Silicon monolithic integrated circuit
.www.rohm.com
© 2013 ROHM Co., Ltd. All rights reserved.
TSZ22111・14・001
○This product is not designed protection against radioactive rays
1/17
TSZ02201-0F2F0A200160-1-2
16.Jul.2015 Rev.002
BD7672BG
●Pin Configuration(SSOP6)
Datasheet
(Unit:mm)
Figure 2, External Dimensions of SSOP6 Package
●Pin Description
NO. Pin Name
1 GND
2 FB
3 COMP
4 CS
5 VCC
6 OUT
Table 1 I/O PIN Functions
I/O Function
I/O GND pin
I Feedback signal input pin
I Comparator input pin
I Primary current sensor pin
I Power supply input pin
O External MOS drive pin
ESD protection system
VCC
GND
○-
○○
○○
○○
-○
○○
●I/O Equivalent Circuit
1
GND
GND
2 FB
VCC
FB
RFB
3 COMP
VCC
COMP
RCOMP
4
VCC
CS
CS
5 VCC
VCC
6
VCC
OUT
OUT
Figure 3, I/O Equivalent Circuit
www.rohm.com
© 2013 ROHM Co., Ltd. All rights reserved.
TSZ22111・15・001
2/17
TSZ02201-0F2F0A200160-1-2
16.Jul.2015 Rev.002
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