Rohm BD7672BG-TR Pwm control type dc/dc converter ic for ac/dc driver Datasheet

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
W(Typ) x D (Typ) x H (Max)
2.90mm x 2.80mm x1.25mm
●Package
SSOP6
●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
F2
D4
F1
C2
D1
FL1
ZNR1
C8
R2
R1
+ C5
C9
D2
+ C1
R4
Q1
D3
+
C3
ZD
R5
R6
C7
7673
7672B
U1
C4
R11
R9
R7
C6
R3
R8
U2
R10
Figure 1,
○Product structure：Silicon monolithic integrated circuit
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© 2013 ROHM Co., Ltd. All rights reserved.
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Application Diagram (12 V 1A Isolated Type)
○This product is not designed protection against radioactive rays
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Datasheet
BD7672BG
2B
●Pin Configuration（SSOP6）
(Unit:mm)
Figure 2,
External Dimensions of SSOP6 Package
●Pin Description
Table 1 I/O PIN Functions
NO.
Pin Name
I/O
1
GND
I/O
2
FB
3
4
ESD protection system
Function
VCC
GND
GND pin
○
-
I
Feedback signal input pin
○
○
COMP
I
Comparator input pin
○
○
CS
I
Primary current sensor pin
○
○
5
VCC
I
Power supply input pin
-
○
6
OUT
O
External MOS drive pin
○
○
●I/O Equivalent Circuit
GND
1
2
COMP
3
FB
VCC
VCC
GND
RFB
FB
4
CS
5
RCOMP
COMP
VCC
6
OUT
VCC
VCC
CS
VCC
OUT
Figure 3, I/O Equivalent Circuit
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Datasheet
BD7672BG
●Block Diagram
+
VH
FUSE
AC
Diode
Bridge
Filter
85- 265Vac
VO
CM
Rstart
Cvcc
Vs
VCC
+
-
VCC UVLO
13.5V / 7.5V
+
-
Internal Block
4.0V LineReg
VCC OVP
LATCH
(27.5V)
4.0V
LineReg
Soft Start
0～1msec Maxduty 15%
1～8msec Maxduty 25%
25.9kΩ
+
COMP
0.5V
S
4.0V LineReg
R
OUT
Q1
O SC
OLP
Comparator
+
DRIVER
PWM Control
20kΩ
FB
Q
Timer
( 250 ms)
+
-
Pulse Skip
Comparator
-
CS
Current Limit
Comparator
+
PWM
Comparator
Leading Edge
Blanking
(typ=250ns)
Rs
MAX
DUTY
+
Frequency
hopping
+
OSC = 65 kHz
Slope
Compensation
GND
FeedBack
With
Isolation
Figure 4, Block Diagram
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Datasheet
BD7672BG
●Description of Each Block
( 1 ) Start Sequences (Soft Start Operation, Light Load Operation, and Overload Protection)
Start sequences are shown in Figure 5. This is also shown the operation of overload protection.
See the sections below for detailed descriptions
VH
VCC=13.5V
VCC＝7.5V
VCC＝7.0V
VCC
Within
250ms
Internal REF
Pull Up
250ms
FB
Over Load
Vout
Normal Load
Light LOAD
Iout
Burst mode
Switching
stop
Switing
Soft Start
Switching
A
E
F
B C
D
Figure 5, Start Sequence Timing Chart
G H
I
J
A: Input voltage VH is applied
B: VCC pin voltage rises by being supplied from VH line through start resistor “Rstart” and the IC starts operating when VCC >
VUVLO1 (13.5V Typ).
Switching operation starts when other protection functions are judged as normal.
From startup to be stable output voltage, application should be set to stabilize output voltage during VCC > VUVLO2 (7.5V Typ)
because the VCC pin consumption current causes the VCC voltage drop.
C: Operated soft start function, maximum duty is restricted to 15% during a 1ms period to prevent any excessive rise in voltage
or current. From 1ms to 8ms, maximum duty is restricted to 25%. Maximum duty is restricted to 75% after 8ms.
D: VOUT voltage rises when the switching operation starts.
Once the output voltage starts, it is set to the rated voltage level within the TFOLP period (250ms Typ).
The output voltage is regulated within TFOLP (=250ms Typ) from starting.
E: During Light Load, when FB pin voltage < VBST (=0.3V Typ), Burst method is operated to keep power consumption down.
F: Over Load condition occurs when FB pin voltage > VFOLP1A (=3.6V Typ).
G: When FB pin voltage is at VFOLP1A (= 3.6V Typ) for more than TFOLP (250ms Typ), the overload protection function is triggered
and switching is stopped. The IC’s internal 250ms timer is reset during the TFOLP period (250ms Typ) if FB < VFOLP1B even
once.
H: If the VCC voltage drops to VUVLO2 (7.5V typ) or below, restart is executed.
I: The IC’s circuit current is reduced and the VCC pin value rises. (Same as B).
J: Same as D
In Figure 4, start resistor Rstart is needed to start the application.
When the start resistor Rstart value is reduced, standby power is increased and the startup time is shortened.
Conversely, when the start resistor Rstart value is increased, standby power is reduced and the startup time is lengthened.
Standby current is less than 20uA at VCC UVLO is disable, and it can calculate VCC UVLO voltage from VUVLO1=14.5V
(Max).
ex） Starting resistor Rstart setting method;
Rstart = (VHmin - VUVLO1（Max）) / IOFF（Max）
In the case of Vac=100V (-20% of a margin), Rstart requirement can be found by the following formulas:
VHmin =100 × √2 × 0.8 = 113V
Because of VUVLO1 (Max) =14.5V, Rstart ≦ (113V - 14.5V) / 20μA＝4.975MΩ
Start-up time can be found by the following formulas:
Tstart = -Rstart × CVCC × ln (1-VUVLO1/VHmin)
ex）Rstart=3.0MΩ
2
2
Rstart resistor loss in this case is : Pd (Rstart) = (VH-VCC) / Rstart = (141V - 14.5V) / 3.0M = 5.35mW.
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Datasheet
BD7672BG
( 2 ) VCC Pin Protection
BD7672BG includes UVLO (Under Voltage Locked Out) and OVP (Over Voltage Protection) functions to monitor VCC pin
voltage (see Figure 6 for OVP latch operation).
The UVLO function prevents damage to MOSFET by stopping switching operations by latch protection when the VCC pin
voltage drops to VCC < VUVLO2 (= 7.5V Typ).
The VCC OVP function prevents damage to MOSFET by stopping switching operations when the VCC pin voltage exceeds
VOVP1 (= 27.5V Typ).
The latch release condition is when VCC < VLATCH (VUVLO2 - 0.5V, Typ = 7.0V). A latch blanking time is used for protecting
mal-function. This time is 100us.
VCC
27.5V
13.5V
7. 5V
7.0V
Time
OUT
Switing
ON
ON
OFF
OFF
Time
100 us
Figure 6, VCC UVLO/OVP Operation (Latch)
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Datasheet
BD7672BG
( 3 ) DCDC Driver (PWM Comparator, Frequency Hopping, Slope Compensation, OSC, Burst)
BD7672BG uses current mode PWM control. In the internal generator, the average switching frequency is 65 kHz.
Furthermore, switching frequency hopping function is built-in while the switching frequency fluctuation is shown as in
Figure 7. Fluctuation cycle is 125Hz (=8ms).
+4kHz
(+6%)
-4kHz
(-6%)
Figure 7,
Frequency Hopping Function
The max-duty cycle is fix to 75% (Typ) at OUT pin and minimum pulse width is fix at 500ns (Typ). When the duty cycle
exceeds 50% at Current Mode control, the sub-harmonic oscillation occurs. To prevent it, IC is built-in slope
compensation function.
BD7672BG has burst mode function to attain less power consumption when load is light. This function monitors FB pin
voltage and detects light load when FB voltage < VBST (=0.3V Typ).
The secondary output voltage, the FB voltage and the DCDC function are shown in Figure 8.
FB pin is pulled up by RFB (=20kΩ Typ). At light load, when the secondary output voltage rises, the FB pin voltage will
drop and when this goes below VBST (=0.3V Typ) burst function will follow to reduce the power consumption.
Overload
Switching frequency
65kHz
Burst
0.3V
Figure 8,
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TSZ22111・15・001
FB PIN Voltage
3.6V
Switching Operation Status Changes by FB Pin Voltage
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Datasheet
BD7672BG
( 4 ) Over Current Limiter and Leading Edge Blanking Period
BD7672BG has over current limiter for each switching cycle.
When the CS pin voltage exceeds the VCS voltage (=0.5V Typ), switching is turned OFF.
In addition, when the driver MOSFET is turned ON, surge current occurs at each capacitor component and drive current.
Therefore, when the CS pin voltage rises temporarily, the detection errors may occur in the over current limiter circuit. To
prevent detection errors, the OUT pin is switched from low to high and the CS signal is blanked for 250nsec by the LEB
(Leading Edge Blanking) function. This blanking function enables a reduction of CS pin noise filtering in response to noise
that occurs when the OUT pin is switched from low to high.
( 5 ) Output Overload Protection Function (FB OLP Comparator )
Overload Protection Function monitors the load status of secondary output through FB pin and stops the switching of OUT
pin during excessive load. In over load condition, there is no current in photo-coupler because output voltage decreases
(drops) while FB pin voltage rises.
When FB pin voltage exceeds VFOLP1A (=3.6V Typ) at TFOLP (=250ms Typ) interval continuously, a load is excessive and
OUT pin is fixed to L. The timer of overload protection is reset when FB pin drops further than VFOLP1B (=3.4V Typ) within
TFOLP (=250ms Typ) after exceeding VFOLP1A (=3.6V Typ). Switching functions within this TFOLP (=250ms Typ).
FB voltage, which is pulled up in resistance to IC internal voltage operates from VFOLP1A (=3.6V Typ) or more at start-up. For
this matter, set the start-up time of the secondary output voltage such that the FB voltage is always VFOLP1B (=3.4V Typ) or
less within TFOLP (=250ms Typ) at start-up.
Figure 9, Overload Protection (Self-restart)
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Datasheet
BD7672BG
( 6 ) COMP Pin External Latch Function
IC is latched when the COMP pin voltage goes below VLATCH (0.5V Typ). A latch timer for TLATCH (100us Typ) added to
prevent operation errors caused by noise.
The COMP pin is pulled up by RCOMP (25.9kΩ Typ), and when RT (3.7kΩ Typ) is pulled down at the COMP pin, latch
protection is operated. Some application examples are shown in Figure 10, Figure 11, and Figure 12.
Resister value R [kΩ]
Overheating Protection by NTC Thermistor
A thermistor is attached to the COMP pin so that latching can be stopped when overheating occurs.
In the case of this application, it should be designed so that the thermistor resistance becomes RT (3.70kΩ Typ) when
overheating is detected.
(Figure 10 and Figure 11 are application circuit examples in which latch operation occurs when Ta = 110℃)
The variation in RT (=3.70kΩ Typ) shown in an electrical property includes only IC.
Please add the variation of external thermistor resistance to it and design.
20.0
18.0
16.0
14.0
12.0
10.0
8.0
6.0
4.0
2.0
0.0
RTt(typ3.7kΩ)
Detect
0
20
40
60
80
100
120
140
160
180
200
Temparature T[℃ ]
Figure 10, COMP Pin Overheating Protection Application
Figure 11, Temperature-Thermistor Resistance Value
Secondary Output Voltage Overvoltage Protection
A photo-coupler is attached to the COMP pin to perform detection of secondary output overvoltage.
Figure 12,
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Datasheet
BD7672BG
●Absolute Maximum Ratings （Ta=25℃）
Parameter
Symbol
Rating
Unit
Maximum Applied Voltage 1
Vmax1
30
V
VCC,
Maximum Applied Voltage 2
Vmax2
6.5
V
CS,
OUT pin output Peak Current
IOUT
±1.0
A
Allowable Dissipation
Pd
674.9 (Note1)
mW
Topr
-40 to +85
o
C
-55 to +150
o
C
Operating Temperature Range
Storage Temperature Range
Tstr
Conditions
OUT
FB,
COMP
When implemented
(Note1) SSOP6: Derate by 6.749 mW/°C when operating above Ta=25°C (when mounted on 70 mm × 70 mm, 1.6 mm thick,
glass epoxy on single-layer substrate).
●Recommended Operating Ratings（Ta=25℃）
Parameter
Symbol
Rating
Unit
VCC
8.5 to 26.0
V
Power Supply Voltage Range
●Electrical Characteristics (Unless otherwise noted, Ta = 25C, VCC=12V)
Specifications
Parameter
Symbol
MIN
TYP
MAX
Conditions
VCC pin voltage
Unit
Conditions
［Circuit Current］
VCC = 12V
(UVLO = Detection)
Circuit Current (OFF)
IOFF
-
12
20
μA
Circuit Current (ON) 1
ION1
-
600
1000
μA
Circuit Current (ON) 2
ION2
-
400
600
μA
(during pulse operation
when OFF)
VCC UVLO Voltage 1
VUVLO1
12.50
13.50
14.50
V
VCC rise
VCC UVLO Voltage 2
VUVLO2
6.50
7.50
8.50
V
VCC drop
VCC UVLO Hysteresis
VUVLO3
-
6.00
-
V
VUVLO3= VUVLO1- VUVLO2
VCC OVP Voltage 1
VOVP1
25.0
27.5
30.0
V
VCC rise
FB = 2.0V COMP: 100kΩ
(during pulse operation)
FB = 0.0V COMP:100kΩ
［VCC Pin Protection Function］
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Datasheet
BD7672BG
●Electrical Characteristics of control block (Unless otherwise noted, Ta = 25C, VCC=12V)
Specifications
Parameter
Symbol
Unit
MIN
TYP
MAX
Conditions
[PWM Type DCDC Driver Block]
Oscillation Frequency
FSW1
60
65
70
KHz
FB=2.0V
average frequency
Frequency Hopping Width 1
FDEL1
-
4.0
-
KHz
FB=2.0V
FCH
93
125
157
Hz
Hopping Fluctuation Frequency
Minimum Pulse Width
Tmin
-
500
-
ns
Soft Start Time 1
TSS1
0.75
1.00
1.25
ms
Soft Start Time 2
TSS2
6.00
8.00
10.00
ms
Maximum Duty 1
Dmax
68.0
75.0
82.0
%
During normal operation
Maximum Duty 2
DSS1
5.0
15.0
25.0
%
During soft start
0[ms] to Tss1[ms]
Maximum Duty 3
DSS2
15.0
25.0
35.0
%
During soft start
TSS1 [ms] to TSS2 [ms]
FB pin Pull-up Resistance
RFB
15
20
25
kΩ
⊿ FB / ⊿ CS Rain
Gain
-
5
-
V/V
FB Burst Voltage
VBST
0.20
0.30
0.40
V
During FB drop
FB OLP Voltage 1a
VFOLP1A
3.3
3.6
3.9
V
When overload is detected
(FB rise)
FB OLP Voltage 1b
VFOLP1B
-
VFOLP1A-0.
2
-
V
When overload is detected
(FB drop)
FB OLP Timer
TFOLP
187
250
312
ms
Latch Release Voltage
(VCC pin voltage)
VLATCH
-
VUVLO2-0.
5
-
V
Latch release voltage
VCCUVLO2-0.5 [V]
Latch Mask Time
TLATCH
50
100
200
us
VCCOVP, COMP
Mask time
Overcurrent Detection Voltage
VCS
0.475
0.500
0.525
V
Leading Edge Blanking Time
TLEB
-
250
-
ns
OUT pin Pch MOS Ron
RPOUT
10
25
39
Ω
OUT pin Nch MOS Ron
RNOUT
7
12
Ω
[Overcurrent Detection Block]
[Output Driver Block]
3
[External Latch Comparator Block]
COMP pin Latch Detection
Voltage
VCOMP
-
0.5
-
V
COMP pin Pull-up Resistance
RCOMP
-
25.9
-
kΩ
RT
3.30
3.70
4.10
kΩ
Thermistor Resistance
Detection Value
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Thermistor connected
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TSZ02201-0F2F0A200160-1-2
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Datasheet
BD7672BG
85.0
83.0
25.0
23.0
68.0
81.0
79.0
77.0
21.0
19.0
17.0
66.0
64.0
62.0
60.0
-40 -25 -10
5
20
35
50
65
MAXDUTY2
(When TYP frequency)[%]
70.0
MAXDUTY1
(When TYP frequency)[%]
TYP FREQ[ｋHz]
●Typical Performance Curves
(This is not a guarantee since this is the reference data. Figure 36 shows the measurement circuit diagram.)
75.0
73.0
71.0
69.0
67.0
65.0
80
-40 -25 -10
Temp[℃ ]
20
35
50
65
80
-40 -25 -10
Figure 14, MAXDUTY1 (With Typ frequency)
20
35
50
65
80
Figure 15, MAXDUTY2 (With Typ frequency）
20
35
50
65
80
MAXDUTY SS2(VCC=15)[msec]
MAXDUTY SS1(VCC=15）[msec]
5
1.30
1.20
1.10
1.00
0.90
0.80
0.70
0.60
-40 -25 -10
Temp[℃ ]
5
20
35
50
65
10.8
10.3
9.8
9.3
8.8
8.3
7.8
7.3
6.8
6.3
5.8
5.3
4.8
80
-40 -25 -10
Temp[℃ ]
Figure 16, MAXDUTY3 (With Typ frequency）
5
20
35
50
65
80
Temp[℃ ]
Figure 17, MAXDUTY SS1 (VCC=15）
Figure 18, MAXDUTY SS2 (VCC=15)
12.0
200.0
11.0
10.0
9.0
8.0
7.0
6.0
5.0
37.0
31.0
28.0
25.0
22.0
19.0
16.0
4.0
13.0
3.0
10.0
-40 -25 -10
5
20
35
50
65
175.0
34.0
TIMER LATCH[us]
PMOS RON(VCC=12)[Ω]
NMOS RON(VCC=12)[Ω]
5
Temp[℃ ]
1.40
35.0
33.0
31.0
29.0
27.0
25.0
23.0
21.0
19.0
17.0
15.0
-40 -25 -10
5
20
35
50
65
80
Temp[℃ ]
125.0
100.0
75.0
-40 -25 -10
5
20
35
50
65
80
Temp[℃ ]
Figure 20, PMOS RON (VCC=12)
Figure 19, NMOS RON (VCC=12)
150.0
50.0
-40 -25 -10
80
Temp[℃ ]
Figure 21, Timer Latch
25.0
FBRES(VCC=12)[kΩ]
20.0
ICC(VCC)OFF(VCC=12)[uA]
9.0
7.0
5.0
Temp[℃ ]
Figure 13, Typ Frequency Fsw1
MAXDUTY3
(When TYP frequency)） [%]
5
15.0
13.0
11.0
15.0
10.0
5.0
23.0
21.0
19.0
17.0
15.0
0.0
-40 -25 -10
5
20
35
50
65
80
Temp[℃ ]
Figure 22, ICC (VCC) OFF (VCC=12)
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-40 -25 -10
5
20
35
50
65
80
Temp[℃ ]
Figure 23, FBRES (VCC=12)
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Datasheet
BD7672BG
0.40
325.0
300.0
275.0
250.0
225.0
200.0
175.0
150.0
-40 -25 -10
5
20
35
50
65
FB Burst Voltage(VCC=12)[V]
0.53
CURLIM VOLTAGE(VCC=12)[V]
FB OVP 256ms(VCC=12)[ms]
350.0
0.52
0.51
0.50
0.49
0.48
-40 -25 -10
80
5
20
35
50
65
0.35
0.30
0.25
0.20
80
-40 -25 -10
Temp[℃ ]
Temp[℃ ]
Figure 24, FB OVP 256ms(VCC=12)
5
20
35
50
65
80
Temp[℃ ]
Figure 25, CURLIM Voltage (VCC=12)
Figure 26, FB Burst Voltage (VCC=12)
0.58
COMP pull up RES(VCC=12)[kΩ]
0.61
3.00
COMP LATCH detect
voltage error[%]
COMP LATCH detect voltage[V]
5.00
0.55
0.52
0.49
0.46
0.43
1.00
‐1.00
‐3.00
0.40
0.37
‐5.00
-40 -25 -10
5
20
35
50
65
80
-40 -25 -10
Temp[℃ ]
5
20
35
50
65
31.4
29.4
27.4
25.4
23.4
21.4
19.4
-40 -25 -10
80
Figure 27, COMP Latch Detect Voltage
5
20
35
50
65
80
Temp[℃ ]
Temp[℃ ]
Figure 28, COMP Latch Detect Voltage Error
Figure 29, COMP Pull-up RES (VCC=12)
5.0
COMP pull up RES
error(VCC=12)[%]
3.0
1.0
‐1.0
‐3.0
‐5.0
-40 -25 -10
5
20
35
50
65
80
Temp[℃ ]
Figure 30, COMP Pull-up RES Error (VCC=12)
Figure 31, RCOMP (VCC=12)
TYP FREQ[kHz]
68.0
66.0
64.0
62.0
60.0
8.5
14.0
19.5
25.0
VCC[V]
Figure 33, Typ Frequency Fsw1 (temp=25℃)
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TSZ22111・15・001
Figure 32, RCOMP Error
0.530
0.525
4.02
0.520
0.515
RCOMP(VCC=12)[kΩ]
CURLIM VOLTAGE(VCC=12)[V]
70.0
0.510
0.505
0.500
0.495
0.490
0.485
3.92
3.82
3.72
3.62
3.52
3.42
3.32
0.480
8.5
14.0
19.5
25.0
VCC[V]
Figure 34, CURLIM Voltage (temp=25℃)
12/17
8.5
14.0
19.5
25.0
VCC[V]
Figure 35, RCOMP (temp=25℃)
TSZ02201-0F2F0A200160-1-2
16.Jul.2015 Rev.002
Datasheet
BD7672BG
BD7672BG
GND
OUT
FB
VCC
COMP
A
A
CS
A
Figure 36, Measurement Circuit Diagram
●Power Dissipation
The thermal design should set the operation for the following conditions.
(Since the temperature shown below is the guaranteed temperature, be sure to take margin into account.)
1. The ambient temperature Ta must be 85℃ or less.
2. The IC’s loss must be within the allowable dissipation Pd.
The thermal reduction characteristics are as follows.
(PCB : 70mm×70mm×1.6mm mounted on glass epoxy substrate)
Figure 37, SSOP6 Thermal Reduction Characteristics
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16.Jul.2015 Rev.002
Datasheet
BD7672BG
●Operational Notes
（1）Absolute Maximum Ratings
Operating the IC over the absolute maximum ratings may damage the IC. In addition, it is impossible to predict all
destructive situations such as short-circuit modes or open circuit modes. Therefore, it is important to consider circuit
protection measures, like adding a fuse, in case the IC is expected to be operated in a special mode exceeding the
absolute maximum ratings.
（2）Power Supply and Ground Lines
Design the PCB layout pattern to provide low impedance ground and supply lines. Separate the ground and supply
lines of the digital and analog blocks to prevent noise in the ground and supply lines of the digital block from affecting
the analog block. Furthermore, connect a capacitor to ground at all power supply pins. Consider the effect of
temperature and aging on the capacitance value when using electrolytic capacitors.
（3）Ground Voltage
The voltage of the ground pin must be the lowest voltage of all pins of the IC at all operating conditions. Ensure that
no pins are at a voltage below the ground pin at any time, even during transient condition.
（4）Short between pins and mounting errors
Be careful when mounting the IC on printed circuit boards. The IC may be damaged if it is mounted in a wrong
orientation or if pins are shorted together. Short circuit may be caused by conductive particles caught between the
pins.
（5）Operation under strong magnetic fields
Operating the IC in the presence of a strong electromagnetic field may cause the IC to malfunction.
（6）Regarding input pins of the IC
Parasitic diodes inevitably occur in the structure of the IC. The operation of parasitic diodes can result in mutual
interference among circuits, operational faults, or physical damage. Therefore, conditions that causes these diodes to
operate, such as applying a voltage lower than the GND voltage to an input pin (and thus to the P substrate) should
be avoided. Also, do not apply voltage to an input pin when there is no power supply voltage being applied to the IC.
In fact, even if a power supply voltage is being applied, the voltage applied to each input pin should be either below
the power supply voltage or within the guaranteed values in the electrical characteristics.
（7）External capacitors
When using a ceramic capacitor, determine the dielectric constant considering the change of capacitance with
temperature and the decrease in nominal capacitance due to DC bias and others.
（8）Thermal Consideration
Use a thermal design that allows for a sufficient margin by taking into account the permissible power dissipation (Pd)
in actual operating conditions.
Also, use these products within ranges that do not put output Tr beyond the rated voltage and ASO.
（9）Rush current
In a CMOS IC, momentary rush current may flow if the internal logic is undefined when the power supply is turned
ON, so caution is needed with regard to the power supply coupling capacitance, the width of power supply and GND
pattern wires, and how they are laid out.
（10）Unused input terminals
Input terminals of an IC especially logic inputs are often connected to the gate of a CMOS transistor. The gate has
extremely high impedance and extremely low capacitance. It can be easily charged by the electric field from the
outside if left unconnected. The small charge acquired in this way is enough to produce a significant effect on the
conduction through the transistor and cause unexpected operation of IC. So unless otherwise specified, input
terminals not being used should be connected to the power supply or ground line.
（11）About this Document
Although the functional description and application notes given in this document are reliable, it does not mean that
the particular application a user designs with this IC is guaranteed to work. It is the user's responsibility to check well
the design application including other external devices used together with the IC.
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16.Jul.2015 Rev.002
Datasheet
BD7672BG
●Ordering Information
B
D
7
6
7
2
Part Number
B
G
-
Package
G:SSOP6
TR
Packaging and forming specification
TR: Embossed tape and reel
●Marking Diagram
SSOP6 (TOP VIEW)
2
B
Part Number Marking
1PIN MARK
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TSZ22111・15・001
LOT Number
15/17
TSZ02201-0F2F0A200160-1-2
16.Jul.2015 Rev.002
Datasheet
BD7672BG
●Physical Dimension, Tape and Reel Information
Package Name
SSOP-6
<Tape and Reel information>
Tape
Embossed carrier tape
Quantity
3000pcs
Direction
of feed
TR
The direction is the 1pin of product is at the upper right when you hold
( reel on the left hand and you pull out the tape on the right hand
)
1pin
Direction of feed
Reel
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∗ Order quantity needs to be multiple of the minimum quantity.
16/17
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16.Jul.2015 Rev.002
Datasheet
BD7672BG
●Revision History
Date
Revision
2013.5.28
001
2015.7.16
002
Changes
New preparation
Page. 01 Modify circuit Figure1
Page. 04 Modify Figure4
Page. 06 Modify written error
Page. 06 Modify circuit Figure6
Page. 08 Modify written error
Page. 09 Modify written error
Page. 10 Modify t written error
Page. 13 Modify circuit Figure36
Page. 13 Modify circuit Figure37
Page. 16 Move Physical dimension page
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16.Jul.2015 Rev.002
Datasheet
Notice
Precaution on using ROHM Products
1.
Our Products are designed and manufactured for application in ordinary electronic equipments (such as AV equipment,
OA equipment, telecommunication equipment, home electronic appliances, amusement equipment, etc.). If you
(Note 1)
, transport
intend to use our Products in devices requiring extremely high reliability (such as medical equipment
equipment, traffic equipment, aircraft/spacecraft, nuclear power controllers, fuel controllers, car equipment including car
accessories, safety devices, etc.) and whose malfunction or failure may cause loss of human life, bodily injury or
serious damage to property (“Specific Applications”), please consult with the ROHM sales representative in advance.
Unless otherwise agreed in writing by ROHM in advance, ROHM shall not be in any way responsible or liable for any
damages, expenses or losses incurred by you or third parties arising from the use of any ROHM’s Products for Specific
Applications.
(Note1) Medical Equipment Classification of the Specific Applications
JAPAN
USA
EU
CHINA
CLASSⅢ
CLASSⅡb
CLASSⅢ
CLASSⅢ
CLASSⅣ
CLASSⅢ
2.
ROHM designs and manufactures its Products subject to strict quality control system. However, semiconductor
products can fail or malfunction at a certain rate. Please be sure to implement, at your own responsibilities, adequate
safety measures including but not limited to fail-safe design against the physical injury, damage to any property, which
a failure or malfunction of our Products may cause. The following are examples of safety measures:
[a] Installation of protection circuits or other protective devices to improve system safety
[b] Installation of redundant circuits to reduce the impact of single or multiple circuit failure
3.
Our Products are designed and manufactured for use under standard conditions and not under any special or
extraordinary environments or conditions, as exemplified below. Accordingly, ROHM shall not be in any way
responsible or liable for any damages, expenses or losses arising from the use of any ROHM’s Products under any
special or extraordinary environments or conditions. If you intend to use our Products under any special or
extraordinary environments or conditions (as exemplified below), your independent verification and confirmation of
product performance, reliability, etc, prior to use, must be necessary:
[a] Use of our Products in any types of liquid, including water, oils, chemicals, and organic solvents
[b] Use of our Products outdoors or in places where the Products are exposed to direct sunlight or dust
[c] Use of our Products in places where the Products are exposed to sea wind or corrosive gases, including Cl2,
H2S, NH3, SO2, and NO2
[d] Use of our Products in places where the Products are exposed to static electricity or electromagnetic waves
[e] Use of our Products in proximity to heat-producing components, plastic cords, or other flammable items
[f] Sealing or coating our Products with resin or other coating materials
[g] Use of our Products without cleaning residue of flux (even if you use no-clean type fluxes, cleaning residue of
flux is recommended); or Washing our Products by using water or water-soluble cleaning agents for cleaning
residue after soldering
[h] Use of the Products in places subject to dew condensation
4.
The Products are not subject to radiation-proof design.
5.
Please verify and confirm characteristics of the final or mounted products in using the Products.
6.
In particular, if a transient load (a large amount of load applied in a short period of time, such as pulse. is applied,
confirmation of performance characteristics after on-board mounting is strongly recommended. Avoid applying power
exceeding normal rated power; exceeding the power rating under steady-state loading condition may negatively affect
product performance and reliability.
7.
De-rate Power Dissipation (Pd) depending on Ambient temperature (Ta). When used in sealed area, confirm the actual
ambient temperature.
8.
Confirm that operation temperature is within the specified range described in the product specification.
9.
ROHM shall not be in any way responsible or liable for failure induced under deviant condition from what is defined in
this document.
Precaution for Mounting / Circuit board design
1.
When a highly active halogenous (chlorine, bromine, etc.) flux is used, the residue of flux may negatively affect product
performance and reliability.
2.
In principle, the reflow soldering method must be used on a surface-mount products, the flow soldering method must
be used on a through hole mount products. If the flow soldering method is preferred on a surface-mount products,
please consult with the ROHM representative in advance.
For details, please refer to ROHM Mounting specification
Notice-PGA-E
© 2015 ROHM Co., Ltd. All rights reserved.
Rev.001
Datasheet
Precautions Regarding Application Examples and External Circuits
1.
If change is made to the constant of an external circuit, please allow a sufficient margin considering variations of the
characteristics of the Products and external components, including transient characteristics, as well as static
characteristics.
2.
You agree that application notes, reference designs, and associated data and information contained in this document
are presented only as guidance for Products use. Therefore, in case you use such information, you are solely
responsible for it and you must exercise your own independent verification and judgment in the use of such information
contained in this document. ROHM shall not be in any way responsible or liable for any damages, expenses or losses
incurred by you or third parties arising from the use of such information.
Precaution for Electrostatic
This Product is electrostatic sensitive product, which may be damaged due to electrostatic discharge. Please take proper
caution in your manufacturing process and storage so that voltage exceeding the Products maximum rating will not be
applied to Products. Please take special care under dry condition (e.g. Grounding of human body / equipment / solder iron,
isolation from charged objects, setting of Ionizer, friction prevention and temperature / humidity control).
Precaution for Storage / Transportation
1.
Product performance and soldered connections may deteriorate if the Products are stored in the places where:
[a] the Products are exposed to sea winds or corrosive gases, including Cl2, H2S, NH3, SO2, and NO2
[b] the temperature or humidity exceeds those recommended by ROHM
[c] the Products are exposed to direct sunshine or condensation
[d] the Products are exposed to high Electrostatic
2.
Even under ROHM recommended storage condition, solderability of products out of recommended storage time period
may be degraded. It is strongly recommended to confirm solderability before using Products of which storage time is
exceeding the recommended storage time period.
3.
Store / transport cartons in the correct direction, which is indicated on a carton with a symbol. Otherwise bent leads
may occur due to excessive stress applied when dropping of a carton.
4.
Use Products within the specified time after opening a humidity barrier bag. Baking is required before using Products of
which storage time is exceeding the recommended storage time period.
Precaution for Product Label
QR code printed on ROHM Products label is for ROHM’s internal use only.
Precaution for Disposition
When disposing Products please dispose them properly using an authorized industry waste company.
Precaution for Foreign Exchange and Foreign Trade act
Since concerned goods might be fallen under listed items of export control prescribed by Foreign exchange and Foreign
trade act, please consult with ROHM in case of export.
Precaution Regarding Intellectual Property Rights
1.
All information and data including but not limited to application example contained in this document is for reference
only. ROHM does not warrant that foregoing information or data will not infringe any intellectual property rights or any
other rights of any third party regarding such information or data.
2.
ROHM shall not have any obligations where the claims, actions or demands arising from the combination of the
Products with other articles such as components, circuits, systems or external equipment (including software).
3.
No license, expressly or implied, is granted hereby under any intellectual property rights or other rights of ROHM or any
third parties with respect to the Products or the information contained in this document. Provided, however, that ROHM
will not assert its intellectual property rights or other rights against you or your customers to the extent necessary to
manufacture or sell products containing the Products, subject to the terms and conditions herein.
Other Precaution
1.
This document may not be reprinted or reproduced, in whole or in part, without prior written consent of ROHM.
2.
The Products may not be disassembled, converted, modified, reproduced or otherwise changed without prior written
consent of ROHM.
3.
In no event shall you use in any way whatsoever the Products and the related technical information contained in the
Products or this document for any military purposes, including but not limited to, the development of mass-destruction
weapons.
4.
The proper names of companies or products described in this document are trademarks or registered trademarks of
ROHM, its affiliated companies or third parties.
Notice-PGA-E
© 2015 ROHM Co., Ltd. All rights reserved.
Rev.001
Datasheet
General Precaution
1. Before you use our Pro ducts, you are requested to care fully read this document and fully understand its contents.
ROHM shall n ot be in an y way responsible or liabl e for fa ilure, malfunction or acci dent arising from the use of a ny
ROHM’s Products against warning, caution or note contained in this document.
2. All information contained in this docume nt is current as of the issuing date and subj ect to change without any prior
notice. Before purchasing or using ROHM’s Products, please confirm the la test information with a ROHM sale s
representative.
3.
The information contained in this doc ument is provi ded on an “as is” basis and ROHM does not warrant that all
information contained in this document is accurate an d/or error-free. ROHM shall not be in an y way responsible or
liable for an y damages, expenses or losses incurred b y you or third parties resulting from inaccur acy or errors of or
concerning such information.
Notice – WE
© 2015 ROHM Co., Ltd. All rights reserved.
Rev.001
Datasheet
BD7672BG - Web Page
Buy
Distribution Inventory
Part Number
Package
Unit Quantity
Minimum Package Quantity
Packing Type
Constitution Materials List
RoHS
BD7672BG
SSOP6
3000
3000
Taping
inquiry
Yes