Datasheet
0.75V to VCC-1V, 3A 1ch
Ultra Low Dropout Linear Regulator
BD3508MUV
Key Specifications
General Description
BD3508MUV is an ultra-low-dropout linear chipset
regulator that can operate from a very low input supply
voltage. The product offers ideal performance at low
input voltage and low output voltage applications. A
built-in N-channel MOSFET is incorporated to minimize
the input-to-output differential voltage across the ON
resistance (RON =100mΩ (Max)). This lower dropout
voltage ensures high output current (IOUTMAX=3.0A) and
reduces conversion loss, and thereby eliminates the
need for a switching regulator, its power transistor,
choke coil, and rectifier diode. BD3508MUV is designed
with significant package profile downsizing and reducing
cost. External resistors allow a wide range of output
voltage configurations from 0.65 to 2.7V. NRCS
(soft-start) function enables a controlled output voltage
ramp-up, which can be programmed to any required
power supply sequence.
IN Input Voltage Range:
VCC Input Voltage Range:
Output Voltage Range:
Output Current:
ON-Resistance:
Standby Current:
Operating Temperature Range:
Package
0.75V to VCC-1V
4.3V to 5.5V
0.65V to 2.7V
3.0A (Max)
65mΩ(Typ)
0µA (Typ)
-10°C to +100°C
W(Typ) x D(Typ) x H(Max )
Features
High-precision internal reference voltage circuit
(0.65V±1%)
Built-in VCC under voltage lock out circuit
(VCC=3.80V)
NRCS (soft-start) function for reduction of in-rush
current
Internal N-channel MOSFET driver offers low ON
resistance
Built-in current limiter circuit (3.0A Min)
Built-in thermal shutdown (TSD) circuit
Tracking function
VQFN020V4040
4.00mm x 4.00mm x 1.00mm
Applications
Notebook computers, Desktop computers, LCD-TV,
DVD, Digital appliances
Typical Application Circuit and Block Diagram
VCC
6
VCC
8
VCC
EN
7
UVLO
Reference
Block
Current
Limit
CL
9
10
IN1
IN2
IN
IN3
VCC
OUT1
16
OUT2
17
18OUT3
CL
UVLO
TSD
EN
Thermal
Shutdown
TSD
19
NRCS
FB
11 GATE
1
20
2
GND
NRCS
○Product structure：Silicon monolithic integrated circuit
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OUT
○This product has no designed protection against radioactive rays
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BD3508MUV
Pin Configuration
Pin Descriptions
TOP VIEW
N.C
N.C
N.C
15
14
13
N.C GATE
12
11
OUT1 16
10
OUT2 17
9
IN3
IN2
FIN
OUT3 18
8
FB 19
7
NRCS 20
6
1
2
3
GND1 GND2 N.C
IN1
EN
VCC
Pin No.
Pin Name
PIN Function
1
GND1
Ground pin 1
2
GND2
Ground pin 2
3
N.C.
No connection (empty) pin (Note)
4
N.C.
No connection (empty) pin (Note)
5
N.C.
No connection (empty) pin (Note)
6
VCC
Power supply pin
7
EN
Enable input pin
8
IN1
Input pin 1
9
IN2
Input pin 2
10
IN3
Input pin 3
11
GATE
12
N.C.
No connection (empty) pin (Note)
13
N.C.
No connection (empty) pin (Note)
Gate pin
4
5
14
N.C.
No connection (empty) pin (Note)
N.C
N.C
15
N.C.
No connection (empty) pin (Note)
16
OUT1
Output voltage pin 1
17
OUT2
Output voltage pin 2
18
OUT3
Output voltage pin 3
19
FB
20
NRCS
reverse
FIN
Reference voltage feedback pin
In-rush current protection (NRCS)
capacitor connection pin
Connected to heatsink and GND
(Note) Please short N.C to the GND.
Description of Blocks
1.
AMP
This is an error amplifier that functions by comparing the reference voltage (0.65V) with the FB voltage to drive the
output N-channel FET. The frequency characteristics are optimized such that polymer output capacitors can be used
ad rapid transit response can be achieved. The AMP output voltage ranges from GND to VCC. When EN is OFF, or
when UVLO is active, the output goes LOW and the output N-channel FET switches OFF.
2.
EN
EN is a logic input pin which controls the regulator ON or OFF. When the regulator is OFF, the circuit current is
maintained at 0µA, minimizing current consumption during standby. When the FET is switched ON, the discharge of
NRCS and OUT is enabled, draining the excess charge and preventing the load IC from malfunctioning. Since no
electrical connection is required (such as between the VCC pin and the ESD prevention diode), module operation is
independent of the input sequence.
3.
UVLO
To prevent malfunction that can occur when there is a brief decrease in VCC supply voltage, the UVLO circuit switches
the output OFF. Like EN, UVLO discharges the NRCS and OUT. Once the UVLO threshold voltage (typ 3.80V) is
exceeded, UVLO turns the output ON.
4.
Current Limit
When the output is ON and the output current exceeds the set current limit threshold (0.6A or more), the output voltage
is attenuated to protect the IC on the load side. When current decreases, the output voltage is restored to the allowable
value.
5.
NRCS
The soft-start function can be accomplished by connecting an external capacitor across the NRCS pin and the target
ground. Output ramp-up can be set to any period up to the time the NRCS pin reaches V FB (0.65V). During startup, the
NRCS pin serves as a 20µA (typ) constant current source and charges the external capacitor.
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BD3508MUV
6.
TSD (Thermal Shut Down)
The Thermal Shutdown (TSD) circuit automatically switches output OFF when the chip temperature becomes too high,
protecting the IC against thermal runaway and heat damage. Since the TSD circuit shuts down the IC during extreme
heat conditions, in order to avoid potential problems with the TSD, during thermal design, it is crucial that Tj(max)
parameter is not exceeded.
7.
IN
The IN line acts as the major current supply line, and is connected to the output N-Channel FET drain. Since there is
no electrical connection with the VCC terminal, as in the case when an ESD diode is connected, so its operation does
not depend on the input sequence. However, because of the body diode of the output N-Channel FET, there is
electrical connection (diode connection) between IN and OUT. Consequently, when the output is turned ON and OFF
by IN, reverse current flows, in which case care must be taken.
Absolute Maximum Ratings (Ta=25°C)
Parameter
Input Voltage 1
Input Voltage 2
Enable Input Voltage
Power Dissipation 1
Power Dissipation 2
Power Dissipation 3
Power Dissipation 4
Operating Temperature Range
Storage Temperature Range
Maximum Junction Temperature
Symbol
VCC
VIN
VEN
Pd1
Pd2
Pd3
Pd4
Topr
Tstg
Tjmax
Rating
6.0 (Note 1)
6.0 (Note 1)
6.0
0.34 (Note 2)
0.70 (Note 3)
2.21 (Note 4)
3.56 (Note 5)
-10 to +100
-55 to +125
+150
Unit
V
V
V
W
W
W
W
°C
°C
°C
(Note 1) Should not exceed Pd.
(Note 2) Derating in done 2.7mV/°C for operating above Ta ≥ 25°C no heat sink
(Note 3) Derating in done 5.6mV/°C for operating above Ta ≥ 25°C
PCB size:74.2mm x 74.2mm x 1.6mm when mounted on a 1-layer glass epoxy board(copper foil area : 10.29mm 2)
(Note 4) Derating in done 17.7mV/°C for operating above Ta ≥ 25°C
PCB size:74.2mm x 74.2mm x 1.6mm when mounted on a 4-layer glass epoxy board(copper foil area : front and reverse 10.29mm 2 , 2nd and 3rd
5505mm2)
(Note 5) Derating in done 28.5mV/°C for operating above Ta ≥ 25°C
PCB size:74.2mm x 74.2mm x 1.6mm when mounted on a 4-layer glass epoxy board(copper foil area : each 5505mm 2)
Caution: Operating the IC over the absolute maximum ratings may damage the IC. The damage can either be a short circuit between pins or an open circuit
between pins and the internal circuitry. Therefore, it is important to consider circuit protection measures, such as adding a fuse, in case the IC is operated over
the absolute maximum ratings.
Recommended Operating Conditions (Ta=25°C)
Parameter
Input Voltage 1
Input Voltage 2
Output Voltage setting Range
Enable Input Voltage
NRCS Capacity
Symbol
VCC
VIN
VOUT
VEN
CNRCS
Rating
Min
4.3
0.75
VFB
-0.3
0.001
Max
5.5
VCC-1 (Note 6)
2.7
+5.5
1
Unit
V
V
V
V
µF
(Note 6) VCC and IN do not have to be implemented in the order listed.
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BD3508MUV
Electrical Characteristics
(Unless otherwise specified, Ta=25°C VCC=5V VEN=3V VIN=1.8V R1=3.9kΩ R2=3.3kΩ)
Limit
Parameter
Symbol
Unit
Min
Typ
Max
Circuit Current
VCC Shutdown Mode Current
ICC
-
0.7
1.4
mA
Conditions
IST
-
0
10
µA
Output Voltage
VOUT
-
1.200
-
V
Maximum Output Current
IOUT
3.0
-
-
A
Output Short Circuit Current
Output Voltage Temperature
Coefficient
Feedback Voltage 1
IOST
-
-
4.0
A
Tcvo
-
0.01
-
%/°C
VFB1
0.643
0.650
0.657
V
Feedback Voltage 2
VFB2
0.630
0.650
0.670
V
Line Regulation 1
Reg.l1
-
0.1
0.5
%/V
IOUT=0A to 3A
Tj=-10°C to +100°C
VCC=4.3V to 5.5V
Line Regulation 2
Reg.l2
-
0.1
0.5
%/V
VIN=1.2V to 3.3V
Load Regulation
Minimum Input-Output Voltage
Differential
Standby Discharge Current
Reg.L
-
0.5
10
mV
dVo
-
65
100
mV
IDEN
1
-
-
mA
IOUT=0 to 3A
IOUT=1A,VIN=1.2V
Tj=-10°C to 100°C
VEN=0V, VOUT=1V
VENHI
2
-
-
V
VENLOW
-0.2
-
+0.8
V
IEN
-
7
10
µA
IFB
-100
0
+100
nA
NRCS Charge Current
INRCS
14
20
26
µA
VNRCS=0.5V
NRCS Standby Voltage
VSTB
-
0
50
mV
VEN=0V
VCCUVLO
3.5
3.8
4.1
V
VCCHYS
100
160
220
mV
VCC: Sweep-down
Gate Source Current
IGSO
1.0
1.6
-
mA
VFB=0, VGATE=2.5V
Gate Sink Current
IGSI
3.0
4.7
-
mA
VFB=VCC, VGATE=2.5V
[ENABLE]
Enable Pin
Input Voltage High
Enable Pin
Input Voltage Low
Enable Input Bias Current
VEN=0V
VOUT=0V
(Note 7)
(Note 7)
VEN=3V
[FEEDBACK]
Feedback Pin Bias Current
[NRCS]
[UVLO]
VCC Under voltage Lock Out
Threshold Voltage
VCC Under Voltage Lock Out
Hysteresis Voltage
[AMP]
VCC: Sweep-up
(Note 7) Not 100% tested
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BD3508MUV
Typical Waveforms
VOUT
VOUT
50mV/div
45mV
50mV/div
IOUT
2A/div
3.0A
3.0A
IOUT=0A to 3A/3µsec
IOUT
2A/div
IOUT=0A to 3A/3µsec
t(5µsec/div)
Figure 1. Transient Response
(0A to 3A)
COUT=150µF x 2, CFB=0.01µF
t(5µsec/div)
Figure 2. Transient Response
(0A to 3A)
COUT=150µF
VOUT
50mV/div
VOUT
100mV/div
64mV
55mV
91mV
IOUT
2A/div
IOUT
2A/div
3.0A
3A
IOUT=0A to 3A/3µsec
IOUT=3A to 0A/3µsec
t(5µsec/div)
Figure 3. Transient Response
(0A to 3A)
COUT=47µF, CFB=0.01µF
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t(5µsec/div)
Figure 4. Transient Response
(3A to 0A)
COUT=150µF x 2
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BD3508MUV
Typical Waveforms – continued
VOUT
50mV/div
IOUT
2A/div
VOUT
100mV/div
79mV
IOUT
2A/div
3.0A
IOUT=3A to 0A/3µsec
t(5µsec/div)
87mV
3A
IOUT=3A to 0A/3µsec
Figure 5. Transient Response
(3A to 0A)
COUT=150µF
t(5µsec/div)
Figure 6. Transient Response
(3A to 0A)
COUT=47µF
VEN
2V/div
VEN
2V/div
VNRCS
2V/div
VNRCS
2V/div
VOUT
1V/div
VOUT
1V/div
t(200µsec/div)
t(2msec/div)
Figure 7. Waveform at Output Start
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Figure 8. Waveform at Output OFF
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BD3508MUV
Typical Waveforms – continued
VCC
VCC
VEN
VEN
VIN
VIN
VOUT
VOUT
VCC to VIN to VEN
VIN to VCC to VEN
Figure 9. Input Sequence
Figure 10. Input Sequence
VCC
VCC
VEN
VEN
VIN
VIN
VOUT
VOUT
VCC to VEN to VIN
VEN to VCC to VIN
Figure 12. Input Sequence
Figure 11. Input Sequence
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BD3508MUV
Typical Waveforms – continued
VCC
VCC
VEN
VEN
VIN
VIN
VOUT
VOUT
VIN to VEN to VCC
VEN to VIN to VCC
Figure 13. Input Sequence
Figure 14. Input Sequence
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BD3508MUV
Typical Performance Curves
1.00
Circuit Current
: ICC (mA)
ICC(mA)
Output Voltage : VOUT (V)
0.95
0.90
0.85
0.80
0.75
0.70
0.65
0.60
0.55
0.50
100
-10
Temperature : Ta (°C)
10
30
50
70
90 100
Temperature
Ta(℃) : Ta (°C)
Figure 15. Output Voltage vs Temperature
(IOUT=0mA)
Figure 16. Circuit Current vs Temperature
2.0
1.9
1.8
IIN (mA)
IIN(mA)
IST (µA)
1.7
1.6
1.5
1.4
1.3
1.2
1.1
1.0
-10
Temperature : Ta (°C)
30
50
70
90 100
Temperature
Ta(℃): Ta (°C)
Figure 17. IST vs Temperature
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10
Figure 18. IIN vs Temperature
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BD3508MUV
Typical Performance Curves – continued
25
IINSTB (µA)
NRCS Charge
Current : INRCS (µA)
INRCS(uA)
24
23
22
21
20
19
18
17
16
15
-10
Temperature : Ta (°C)
15
9
Enable InputIen(uA)
Bias Current : IEN (µA)
Feedback PinIFBias
Current : IFB (nA)
B(nA)
10
10
5
0
-5
-10
90 100
7
6
5
4
3
2
1
-20
-10
0
-10
90 100
Figure 21. Feedback Pin Bias Current vs Temperature
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70
8
-15
50
70
Temperature
:
Ta
(°C)
Ta(℃)
50
Figure 20. NRCS Charge Current vs Temperature
20
30
30
Temperature
Ta(℃): Ta (°C)
Figure 19. IINSTB vs Temperature
10
10
10/22
10
30
50
70
Temperature
Ta(℃): Ta (°C)
90 100
Figure 22. Enable Pin Bias Current vs Temperature
TSZ02201-0J2J0A601100-1-2
02.Nov.2015 Rev.001
BD3508MUV
Typical Performance Curves – continued
60
50
40
1.8V
RON (mΩ)
Ω)
RON
(mΩ)
RO
N(m
2.5V
30
20
1.2V
10
0
-10
10
30
50
70
90 100
Input Voltage : VCC (V)
Temperature
: Ta (°C)
Ta(℃)
Figure 23. RON vs Temperature
(VCC=5V/VOUT=1.2V)
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Figure 24. RON vs Input Voltage
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BD3508MUV
Timing Chart
EN
ON/OFF
IN
VCC
EN
0.65V(typ)
NRCS
Start up
VOUT x 0.9V(typ)
OUT
t
VCC ON/OFF
IN
UVLO
Hysteresis
VCC
EN
0.65V(typ)
NRCS
Start up
VOUT x 0.9V(typ)
OUT
t
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BD3508MUV
Application Information
1. Evaluation Board
■ Evaluation Board Schematic
JP14B
NRCS
RF2
GATE
11
12
NC
13
NC
14
R18
VIN
C8
FB
EN
C9
VCC
20
NRCS
C20
1
JPF2
VCC
C10
C12
VCC
EN
SW1
7
C7
R7
VCC
6
C6
5 NC
R19
VIN_S
IN1 8
NC
JPF1
C15
IN3 10
U1
BD3508MUV
4
VCC
TP2
U3
BU4S584G2
RF1
OUT3
19
FB(S)
TP1
18
NC
CFB
GATE
IN2 9
3
C17
R15
OUT2
GND2
C16
U2
MOSFET
OUT1
17
NC
15
NC
VO_S
16
GND1
RLD
R11
JP13B
2
VO
JP13A
JP14A
C11
JP3
PGOOD
R4
JP4B
GND_S
RF3
CF
GND
GND
JP4A
C5
VDD
VPGOOD
VCC
Evaluation Board Standard Component List
Component
U1
C6
C8
C16
C20
Rating
1µF
10µF
22µF
0.01µF
Manufacturer
ROHM
MURATA
MURATA
KYOCERA
MURATA
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Product Name
BD3508MUV
GRM188B11A105KD
GRM21BB10J106KD
CM315W5R226K06AT
GRM188B11H103KD
13/22
Component
R7
R18
R19
CFB
-
Rating
0Ω
3.9kΩ
2.2kΩ
0.01µF
-
Manufacturer
ROHM
ROHM
MURATA
-
Product Name
Jumper
MCR03EZPF5101
MCR03EZPF3901
GRM188B11H103KD
-
TSZ02201-0J2J0A601100-1-2
02.Nov.2015 Rev.001
BD3508MUV
■ Evaluation Board Layout
Silk Screen (Top)
Silk Screen (Bottom)
Middle Layer_1
Middle Layer_2
TOP Layer
Bottom Layer
2. Recommended Circuit Example
Vo
15
C16
C18
14
13
12
11
C8
16
10
17
9
18
8
19
7
20
6
VIN
R18
R19
C20
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1
2
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3
4
5
VEN
C6
VCC
TSZ02201-0J2J0A601100-1-2
02.Nov.2015 Rev.001
BD3508MUV
Component
Recommended
Value
Programming Notes and Precautions
R18/R19
3.6k / 3.9k
IC output voltage can be set by feedback voltage(V FB) and value of output voltage setting
resistance(R18 R19). Output voltage can be computed by VFB x (R18+R19)/R19 but it is
recommended to use at the resistance value(total:about 10kΩ) which is not susceptible to
feedback pin bias current.
22µF
To ensure output voltage stability, OUT1, OUT2, OUT3 should be connected to each
other. In additions, GND pins should also be connected to each other. Output capacitors
play a role in loop gain phase compensation and mitigation of output fluctuation during
rapid changes in load level. Insufficient capacitance may cause oscillation, while high
equivalent series resistance (ESR) will exacerbate output voltage fluctuation under rapid
load change conditions. While a 22µF ceramic capacitor is recommended, actual stability
is highly dependent on temperature and load conditions. Also, note that connecting
different types of capacitors in series may result in insufficient total phase compensation,
thus causing oscillation. Confirm the operation along a variety of temperature and load
conditions.
1µF
The input capacitor reduces the output impedence of the voltage supply connected to the
VCC. When the output impedence of this power supply increases, the input voltage (VCC)
may become unstable. This may result to output oscillation or lower ripple rejection. A low
ESR 1µF capacitor with minimal susceptibility to temperature is preferable, but stability
depends on the power supply characteristics and the substrate wiring pattern. Confirm the
operation across a variety of temperature and load conditions.
10µF
Input capacitors reduce the output impedance of the voltage supply source connected to
the IN input pins. If the impedance of this power supply were to increase, VIN input voltage
could become unstable, leading to oscillation or lowered ripple rejection function. While a
low-ESR 10µF capacitor with minimal susceptibility to temperature is recommended,
stability is highly dependent on the input power supply characteristics and the substrate
wiring pattern. Confirm the operation across a variety of temperature and load conditions.
C20
0.01µF
During power supply start-up, the Non-rush Current on Startup (NRCS) function prevents
rush current flow from IN to OUT through the load, preventing impact on the output
capacitors. Constant current comes from the NRCS pin when EN is HIGH or the UVLO
function is deactivated. The temporary reference voltage is proportional to time, due to the
current charge of the NRCS pin capacitor, and output voltage start-up is proportionate to
this reference voltage. Capacitors with low susceptibility to temperature are
recommended, in order to assure a stable soft-start time.
C18
0.01µF
This component is employed when the C16 capacitor causes, or may cause, oscillation.
This provides more precise internal phase correction.
C16
C6
C8
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BD3508MUV
3. Heat Loss
In thermal design, consider the temperature range wherein the IC is guaranteed to operate and apply appropriate
margins. The temperature conditions that need to be considered are listed below:
(1) Ambient temperature Ta must not exceed 100°C.
(2) Chip junction temperature (Tj) must not exceed 150°C.
Chip junction temperature can be determined as follows:
① Calculation based on ambient temperature (Ta)
Tj Ta j a W
θj-a: VQFN020V4040 367.6°C/W
178.6°C/W
56.6°C/W
35.1°C/W
IC only
1-layer board(copper foil area : 10.29mm2)
4-layer board(copper foil area : front and reverse 10.29mm 2 , 2nd and 3rd 5505mm2)
4-layer board(copper foil area : each 5505mm 2)
Substrate size: 74.2 x 74.2 x 1.6mm3 (substrate with thermal via)
It is recommended to layout the heat radiation VIAs at the GND pattern (at the back of the IC) when there is the GND
pattern in the inner layer (in using multiplayer substrate). However, because this package is very small (size: 4.0mm x
4.0mm) there is no available space to layout the VIA at the bottom of IC. Spreading the pattern and increasing the
number of VIA like the figure below) can achieve superior heat radiation characteristic. (See figure below. the VIA
quantity and size number are designed suitable for the actual situation.)
Most of the heat loss that occurs in BD3508MUV is from the output N-Channel FET. Power loss is determined by the
total VIN -VOUT voltage and output current. In the design, be sure to confirm the system input, output voltage and the
output current conditions in relation to the heat dissipation characteristics of the IN and OUT. Bear in mind that heat
dissipation may vary substantially, depending on the substrate employed because due to the power package
incorporated in BD3508MUV, consider conditions such as substrate size into thermal design.
Power consumption (W) =
Input voltage (VIN) - Output voltage (VOUT)
x IOUT (Ave)
Example) VIN=1.5V, VOUT=1.25V, IOUT(Ave) = 3A
Power consumption W 1.5 V 1.25 V 3.0 A
0.75 W
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BD3508MUV
Power Dissipation
Power Dissipation:Pd [W]
4.0
①3.56W
① 4 layers (Copper foil area : 5505mm2)
copper foil in each layers.
θj-a=35.1°C/W
② 4 layers (Copper foil area front and reverse : 10.29mm2、
2nd and 3rd : 5505mm2)
θj-a=56.6°C/W
③ 1 layer (Copper foil area : 10.29m2)
θj-a=178.6°C/W
④ IC only.
θj-a=367.6°C/W
3.0
②2.21W
2.0
1.0
③0.70W
④0.34W
0
0
25
50
75
100 105 125
150
Ambient temperature:Ta [°C]
I/O Equivalent Circuits
VCC
VCC
VCC
1kΩ
NRCS
1kΩ
VCC
1kΩ
1kΩ
GATE
IN1
1kΩ
IN2
IN3
1kΩ
VCC
VCC
EN
1kΩ
FB
OUT1
OUT2
1kΩ
400kΩ
1kΩ
50kΩ
OUT3
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BD3508MUV
Operational Notes
1.
Reverse Connection of Power Supply
Connecting the power supply in reverse polarity can damage the IC. Take precautions against reverse polarity when
connecting the power supply, such as mounting an external diode between the power supply and the IC’s power
supply pins.
2.
Power Supply Lines
Design the PCB layout pattern to provide low impedance 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
Ensure that no pins are at a voltage below that of the ground pin at any time, even during transient condition.
4.
Ground Wiring Pattern
When using both small-signal and large-current ground traces, the two ground traces should be routed separately but
connected to a single ground at the reference point of the application board to avoid fluctuations in the small-signal
ground caused by large currents. Also ensure that the ground traces of external components do not cause variations
on the ground voltage. The ground lines must be as short and thick as possible to reduce line impedance.
5.
Thermal Consideration
Should by any chance the power dissipation rating be exceeded the rise in temperature of the chip may result in
deterioration of the properties of the chip. In case of exceeding this absolute maximum rating, increase the board size
and copper area to prevent exceeding the Pd rating.
6.
Recommended Operating Conditions
These conditions represent a range within which the expected characteristics of the IC can be approximately
obtained. The electrical characteristics are guaranteed under the conditions of each parameter.
7.
Inrush Current
When power is first supplied to the IC, it is possible that the internal logic may be unstable and inrush current may
flow instantaneously due to the internal powering sequence and delays, especially if the IC has more than one power
supply. Therefore, give special consideration to power coupling capacitance, power wiring, width of ground wiring,
and routing of connections.
8.
Operation Under Strong Electromagnetic Field
Operating the IC in the presence of a strong electromagnetic field may cause the IC to malfunction.
9.
Testing on Application Boards
When testing the IC on an application board, connecting a capacitor directly to a low-impedance output pin may
subject the IC to stress. Always discharge capacitors completely after each process or step. The IC’s power supply
should always be turned off completely before connecting or removing it from the test setup during the inspection
process. To prevent damage from static discharge, ground the IC during assembly and use similar precautions during
transport and storage.
10. Inter-pin Short and Mounting Errors
Ensure that the direction and position are correct when mounting the IC on the PCB. Incorrect mounting may result in
damaging the IC. Avoid nearby pins being shorted to each other especially to ground, power supply and output pin.
Inter-pin shorts could be due to many reasons such as metal particles, water droplets (in very humid environment)
and unintentional solder bridge deposited in between pins during assembly to name a few.
11. Unused Input Pins
Input pins of an IC are often connected to the gate of a MOS transistor. The gate has extremely high impedance and
extremely low capacitance. If left unconnected, the electric field from the outside can easily charge it. 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 the IC. So unless otherwise specified, unused input pins should be connected to the
power supply or ground line.
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BD3508MUV
Operational Notes – continued
12. Regarding the Input Pin of the IC
This monolithic IC contains P+ isolation and P substrate layers between adjacent elements in order to keep them
isolated. P-N junctions are formed at the intersection of the P layers with the N layers of other elements, creating a
parasitic diode or transistor. For example (refer to figure below):
When GND > Pin A and GND > Pin B, the P-N junction operates as a parasitic diode.
When GND > Pin B, the P-N junction operates as a parasitic transistor.
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 cause 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.
Resistor
Transistor (NPN)
Pin A
Pin B
C
E
Pin A
N
P+
P
N
N
P+
N
Pin B
B
Parasitic
Elements
N
P+
N P
N
P+
B
N
C
E
Parasitic
Elements
P Substrate
P Substrate
GND
GND
Parasitic
Elements
GND
Parasitic
Elements
GND
N Region
close-by
Figure 25. Example of monolithic IC structure
13. Area of Safe Operation (ASO)
Operate the IC such that the output voltage, output current, and power dissipation are all within the Area of Safe
Operation (ASO).
14. Thermal Shutdown Circuit(TSD)
This IC has a built-in thermal shutdown circuit that prevents heat damage to the IC. Normal operation should always
be within the IC’s power dissipation rating. If however the rating is exceeded for a continued period, the junction
temperature (Tj) will rise which will activate the TSD circuit that will turn OFF all output pins. When the Tj falls below
the TSD threshold, the circuits are automatically restored to normal operation.
Note that the TSD circuit operates in a situation that exceeds the absolute maximum ratings and therefore, under no
circumstances, should the TSD circuit be used in a set design or for any purpose other than protecting the IC from
heat damage.
BD3508MUV
TSD on Temperature [°C] (typ)
Hysteresis Temperature [°C] (typ)
175
15
15. Output Pin
In the event that load containing a large inductance component is connected to the output terminal, and generation of
back-EMF at the start-up and when output is turned OFF is assumed, it is requested to insert a protection diode.
(Example)
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OUTPUT PIN
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BD3508MUV
Ordering Information
B
D
3
5
0
Part Number
8
M
U
V
-
Package
MUV : VQFN020V4040
E2
Packaging and forming specification
E2: Embossed tape and reel
Marking Diagram
VQFN020V4040 (TOP VIEW)
Part Number Marking
D 3 5 0 8
LOT Number
1PIN MARK
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BD3508MUV
Physical Dimension, Tape and Reel Information
Package Name
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BD3508MUV
Revision History
Date
Revision
02.Nov.2015
001
Changes
New Release
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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 depending on ambient temperature. When used in sealed area, confirm that it is the use in
the range that does not exceed the maximum junction 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.002
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.
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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
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