Rohm BD95710MUV-E2 2phase switching regulator controllers for graphic card Datasheet

Hi-performance Regurator IC Series for PCs
2Phase Switching Regulator
Controllers for Graphic Card
No.09030EBT20
BD95710MUV
●Description
BD95710MUV is a dual-phase switching regulator controller with high output current which can achieve low output voltage (0.4V ~
3.3V) from AC/DC 5V or 12V. High efficiency for the switching regulator can be realized by utilizing an external N-MOSFET power
3
TM
transistor. A new technology called H Reg is a Rohm proprietary control method to realize ultra high transient response against
load change without phase compensation capacitance and resistance. For various applications, it is available to select the 3 types
of N-MOSFET gate drive voltage (12V: for drive ability, 8V: for intermediate drive ability, 5V: for small real estate).
●Features
3
TM
1) H Reg switching Regulator Controller without phase compensation capacitance and resistance
2) Ultra High Tolerance Internal Reference Voltage (+/- 1%)
3) Thermal Shut Down (TSD), Under Voltage LockOut (UVLO), Adjustable Over Current Protection (OCP),
Over Voltage Protection (OVP), Short Circuit protection(SCP) built-in
4) Soft start function to minimize rush current during startup
5) switching Frequency Variable (f=200kHz~1000kHz)
6) Internal Bootstrap Diode
7) High Tolerance Current Balance Function
8) VQFN024V4040 Package (4.0mm x 4.0mm x 1.0mm)
9) Integrated 1-/2-phase switching Function
●Applications
Graphic Cards, Desktop PC, Gaming Equipments, Digital Components
●Maximum Absolute Ratings (Ta=25℃)
Parameter
Input Voltage 1
Input Voltage 2
Input Voltage 3
Input Voltage 4
Input Voltage 5
Input Voltage 6
BOOT Voltage
BOOT-PHASE Voltage
UG-PHASE Voltage
PHASE Voltage
Power Dissipation
Operating Temperature Range
Storage Temperature Range
Junction Temperature
Symbol
VCC
VIN
VCCDRV
5VCC
REFIN/EN
BUSEN
BOOT1/2
BOOT1/2-PHASE
UGATE1/2_
PHASE1/2
Pd1
Topr
Tstg
Tjmax
Limit
15 *1
15 *1
15 *1
7 *1
7 *1*2
7 *1
30 *1
15 *1
15 *1
15
0.34
0～+70
-55～+150
+150
Unit
V
V
V
V
V
V
V
V
V
V
W
℃
℃
℃
*1 Do not to exceed Pd.
*2 REFIN/EN voltage can not go up higher than 5VCC voltage.
●Operating Conditions (Ta=25℃)
Parameter
Input Voltage 1
Input Voltage 2
Input Voltage 5
Input Voltage 6
BOOT Voltage
BOOT-PHASE Voltage
CS Input Voltage
IOUT Setting Resistor
RT Setting Resistor
Symbol
VCC
VIN
REFIN/EN
BUSEN
BOOT1/2
BOOT1/2-PHASE1/2
CSN1/CSP1/CSN2/CSP2
RIOUT
RRT
MIN
4.7
3.3
0.4
0
4.5
4.5
0.4
0
10k
MAX
13.2
13.2
3.3
3.3
27
13.2
3.3
5M
510k
Unit
V
V
V
V
V
V
V
Ω
Ω
* This product should not be used in a radioactive environment.
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© 2009 ROHM Co., Ltd. All rights reserved.
1/20
2009.04 - Rev.B
Technical Note
BD95710MUV
●ELECTRICAL CHARACTERISTICS (Unless otherwise noted, Ta=25℃, VCC=5V, VIN=12V, REF=1.2V, RT=100kΩ)
Standard Value
Unit
Condition
Parameter
Symbol
MIN
TYP
MAX
[Total Block]
Vcc Bias Current
Icc
4
10
mA
Vcc Standby Current
ISTB
1.5
2.0
mA
[5Vcc Block]
5Vcc Output Voltage
5Vcc
4.9
5
5.1
V
5Vcc Output Current
I5Vcc
20
mA
[UVLO Block]
VCC Threshold Voltage
Vcc_UVLO
4.2
4.5
4.7
V Low  High
VCC Hysteresis Voltage
dVcc_UVLO
130
180
230
mV
BUS EN Threshold Voltage
BUS_UVLO
0.6
0.8
0.9
V Low  High
BUS EN Hysteresis Voltage
dBUS_UVLO
5
25
50
mV
5Vcc Threshold Voltage
5Vcc_UVLO
4.1
4.3
4.5
V Low  High
5Vcc Hysteresis Voltage
dVcc_UVLO
100
150
200
mV
[Reference Voltage Block]
Internal Reference Voltage
REFIN/EN
0.594
0.600
0.606
V REFIN/EN=5VCC
REFIN/EN Offset Voltage
REF_IN
REF_IN+10m
V
VoffREFIN/EN REF_IN-10m
REFIN/EN Input Voltage Range
0.4
3.3
V
VREFIN/EN
REFIN/EN Off Threshold Voltage
Vth REFIN/EN
4.5
5Vcc
V
[EN Threshold]
EN Low voltage
Enlow
GND
0.3
V REFIN/EN voltage
EN High voltage
Enhigh
[Operating Frequency]
Oscillation Frequency
FOSC
ON Time
TON
MIN OFF Time
TOffmin
[IREFOUT voltage Block]
IREFOUT Voltage
VIREFOUT
IREFOUT Drive Current
IIREFOUT
[FET Gate Driver Block]
UG high side ON Resistance
RonHGH
UG low side ON Resistance
RonHGL
LG high side ON Resistance
RonLGH
LG high side ON Resistance
RonLGL
[Regulator for VCC]
Output Voltage
VCCDRV
Vcc DRV Drive Current
IVCCDRV
[OCP (Over Current Protection) Block]
Over Current Threshold
OCPTH
[OVP (Over Voltage Protection) Block]
Over Voltage Threshold 1
OVPTH1
Over Voltage Threshold 2
OVPTH2
[SCP (Short Circuit Protection) Block]
SCP Start up Voltage 1
VSCP1
SCP Start up Voltage 2
VSCP2
SCP Delay Time
[POK Detection Block]
POK Threshold 1
TSCP
POKTHLOW1
POK Threshold 2
POKTHLOW2
0.4
-
5Vcc
V
100
-
500
200
400
300
500
kHz
nsec
nsec
1.176
3
1.2
5
1.224
-
V
mA
-
6
4
6
1
12
8
12
2
ohm
ohm
ohm
ohm
7.2
-
8
10
8.8
-
V
mA
0.95
1
1.05
V
VREFx1.25
REFIN/EN
x1.25
VREFx1.3
REFIN/EN
x1.3
VREFx1.35
REFIN/EN
x1.35
V
VREFx0.45
REFIN/EN
x0.45
-
VREFx0.5
REFIN/EN
x0.5
1
VREFx0.55
REFIN/EN
x0.55
-
V
VREFx0.7
VREFIN/EN
x0.70
VREFx0.75
VREFIN/EN
x0.75
VREFx0.80
VREFIN/EN
x0.80
REFIN/EN voltage
REFIN/EN=5Vcc
V
REFIN/EN=5Vcc
V
ms
V
REFIN/EN=5Vcc
V
* Design Guarantee
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2/20
2009.04 - Rev.B
Technical Note
BD95710MUV
●Block Diagram
VIN=12V
+
Vcc
BUSEN
BOOT1
2
5
OFF
VCCDRV
VCC
UGATE1
8VReg
Controller
21
1
Driver
Circuit
BG
22
PHASE1
L1
Vout
24
+
Vcc
5VCC
3
REFIN/EN
15
AGND
3ms
Soft Start
5VReg
0.6V
23
17
4.5V
4
CSP1
CS1CSP2
RT
IMAX/IOUT
PGND
FB
Driver
Circuit
Current
Sense
18
OCP
20
OFF
OFF
1-/2-Phase
switch
BUSEN
VCC
5VCC
UVLO
Control
Logic
13
EN
BG
BUFFER
8
TSD
SCP
EN
FB
REFIN/EN
or
0.3V
Vo REFIN/EN
or
Monitor
0.78V
Vout
OVP
12
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UGATE2
3/20
7
9
6
L2
+
Vcc
14
© 2009 ROHM Co., Ltd. All rights reserved.
VIN_EXT
19
11
IREFOUT
/POK
16
BOOT2
PHASE2
CSN
2
10
+
Vcc
H3RegTM
Controller
Vo
Comp
LGATE1
LGATE2
CSN2
CSN1
CSP2
PHASE2
CSP1
PHASE1
AGND
2009.04 - Rev.B
Technical Note
BD95710MUV
●Pin Configuration
IREFOUT/ REFIN/
PGND FB
UGATE2BOOT2 POK
EN
18
17
16
15
14
13
PHASE2
19
12
LGATE2
20
11 RT
AGND
10 IMAX/
VCCDRV 21
IOUT/
VCC 22
9
CSP2
LGATE1
23
8
CSN2
PHASE
24
7
CS1-
1
UGAT
2
3
BOOT1
4
5
6
5VCC AGND BUSEN CSP1
●Pin Function Table
PIN No.
PIN Name
1
UGATE1
High Side FET Gate Drive Pin 1
2
BOOT1
Supply Voltage for UGATE1
3
5VCC
5V Regulator Output (Iomin=20mA)
4
AGND
Sense GND
5
BUSEN
Bus Enable, Power Supply Monitoring Pin
6
CSP1
Positive Input of Current Sensing 1
7
CSN1
Negative Input of Current Sensing 1
8
CSN2
Negative Input of Current Sensing 2
9
CSP2
10
IMAX / IOUT
11
RT
12
AGND
13
FB
14
PGND
15
REFIN/EN
16
INREFOUT/ POK
PIN Function
Positive Input of Current Sensing 2
Current Limit/Output Current Indication
PHASEitching Frequency Setting
Sense GND
Output Voltage Feedback Pin
Power GND Pin
External Reference Input and Enable Pin
Internal Reference Voltage Output and Power Good Output Pin
17
BOOT2
Supply Voltage for UGATE2
18
UGATE2
High Side FET Gate Drive Pin 2
19
PHASE2
switch Node for Channel 2
20
LGATE2
Low Side FET Gate Drive Pin 2
21
VCCDRV
Driver for External Linear Regulator
22
VCC
23
LGATE1
Low Side FET Gate Drive Pin 1
PHASE1
PHASEitch Node for Channel 1
24
Exposed Pad
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Supply Voltage Pin
FIN
4/20
2009.04 - Rev.B
Technical Note
BD95710MUV
●Pin Descriptions
・UGATE1 (Pin 1), UGATE2 (Pin 18)
These are the voltage supply pins to drive the Gate of the high side FET. This voltage PHASEings between BOOT1/2 and
PHASE1/2. High-speed Gate driving for the high side FET is achieved due to the low on-resistance (3 ohm when UG is high,
2 ohm when UG is low) of the driver.
・BOOT1 (Pin 2), BOOT2 (Pin 17)
These are the voltage supply pins to drive the high side FET. The maximum absolute ratings are 35V (from GND) and 15V
(from PHASE1/2). BOOT1/2 voltages swing between VIN+VCC and VCC during active operation.
・5VCC (Pin 3)
This is the internal 5V regulator output pin. The minimum output current capability is 20mA.
・AGND (Pin 4 , Pin12)
This is the ground pin for IC internal circuits. It is equivalent to FIN voltage.
・BUSEN (Pin 5)
This pin monitors the supply input VIN through resistance divider. The POR rising threshold level is set to 0.8V.
・CsN1 (Pin 6), CsP2 (Pin 9), CsN1 (Pin 7), CsN2 (Pin 8)
These pins are connected to both sides of the current sense resistance or Inductance (DCR sensing) to detect output
current.
・IMAX / IOUT (Pin 10)
This pin has multiple functions such as the output current indication, OCP (Over Current Protection) limit setting, and the
output voltage load line adjustment pin. BD95710MUV detects the voltage between Cs+ pin and Cs- pin and limits the
output current (OCP) using resistance connected between IMAX/IOUT/Droop and GND. A very low current sense resistor or
inductor DCR can also be used for this platform.
・RT (Pin 11)
This is the pin to adjust the switching frequency based on the resistance value. The frequency range is f=50KHz - 1000KHz.
・FB (Pin 13)
This is the output voltage feedback pin. It is possible to adjust the output voltage using external resistor divider based on the
equation, REFIN/EN≒FB. However, FB becomes 0.6V when REFIN/EN=5VCC.
・PGND (Pin 14)
This is the power ground pin connected to the source of the low side FET.
・REFIN/EN/EN (Pin 15)
This is an internal or external reference voltage selectable pin. If REFIN/EN is pulled up to 5VCC, internal reference voltage
(0.6V) is used. If REFIN/EN is driven by an external voltage ranged 0.4V to 3.3V, external voltage of REFIN/EN voltage is
used. It is very convenient for synchronizing external voltage supply. The IC controls the output voltage (REFIN/EN≒FB).
And also this pin is used for enable function. If REFIN/EN is less than 0.3V, the whole circuit is shut down.
・IREFOUT/POK (Pin 16)
This pin is internal reference voltage output and power good output. During start up, this pin voltage is low. This pin
becomes high impedance when FB pin voltage goes beyond 75% of specified FB voltage after soft start ends.
・PHASE1 (Pin 24), PHASE2 (Pin 19)
These are the source pins for the high side FET. The maximum absolute ratings are 15V (from GND). PHASE1/2 voltage
swings between VIN and GND.
・LGATE1 (Pin 23), LGATE2 (Pin 20)
This is the voltage supply to drive the Gate of the low side FET. This voltage swings between VCC and PGND. High-speed
Gate driving for the low side FET is achieved due to the low on-resistance (2 ohm when LGATE1/2 is high, 0.5 ohm when
LGATE1/2 is low) of the driver.
・VCCDRV (Pin 21)
This is the supply voltage pin to drive an external NPN/N_MOSFET for 8V linear regulator. The maximum absolute rating is
15V.
・VCC (Pin 22)
This is the power supply pin for IC internal circuit and driver circuit. The maximum circuit current is 10mA. There are 3
usages depending on a supply voltage for driver (5V, 8V, and 12V). It is recommended that a 0.1uF bypass capacitor be put
in this pin to avoid voltage fluctuation when the VCC is supplied from 5V or 12V rail directly from the actual platforms. If 8V
is used for the supply voltage, this pin is connected to the LDO output. In this case, it is recommended that at least 10uF
ceramic capacitor be input to avoid oscillation.
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5/20
2009.04 - Rev.B
Technical Note
BD95710MUV
●Explanation of Operation
The BD95710MUV is a synchronous buck regulator controller incorporating ROHM’s proprietary H3RegTM CONTROLLA
control system. When VOUT drops due to a rapid load change, the system quickly restores VOUT by extending the TON time
interval. Thus, it serves to improve the regulator’s transient response.
3
TM
H Reg control
(Normal operation)
When FB pin voltage (Vout) falls to a threshold voltage
3
TM
REFIN/EN, the drop is detected, activating the H Reg
CONTROLLA system.
FB
REFIN/EN
REFIN/EN
1
TON=
×
VIN
f
UGAT
[sec]・・・(1)
UGATE ONTIME is determined with the formula above.
LG outputs until the status of VOUT is lower than REF
after the status of UG is off.
UGA
Phase PHASEitch function
VIN_EXT
BUSEN
VOUT
REFIN/
EN
UGAT
UGAT
T
2T
dual-phase
Stand-by
Single-phase
dual-phase
The IC normally operates dual-phase mode, but when the input voltage on the VIN_EXT pin is cut off, the IC latches into
single-phase mode. The IC will remain latched in this mode (even if a voltage is reintroduced onto the VIN_EXT pin) until
the voltage is cycled on any of the EN, VCC or BUSEN pins. It will then return to two-phase mode.
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6/20
2009.04 - Rev.B
Technical Note
BD95710MUV
●Timing Chart
・Soft Start Function
Soft start is activated when REFIN/EN hits its enabling
threshold (VCC, 5VCC, and BUSEN have to be beyond
their own UVLO thresholds). Current control takes effect
at startup, enabling an output voltage “ramping start.”
Soft start timing and incoming current are calculated with
formulas (2) and below.
REFIN/EN
TSS
SS
Soft start time (TSS) ≒ 3msec (fixed)
Incoming current
VOUT
IIN=
IIN
Co×VOUT
3msec
[A] ・・・(2)
(Co: Output capacitor)
・Output Over Voltage Protection
REFIN/EN x 1.3
When the FB pin voltage becomes REFIN/EN x 1.3, the
output over voltage protection is activated and Low side
MOSFET becomes ON to lower the output voltage
(LG=High, UG=Low). When the output voltage goes back
down to the specified level, the whole circuit becomes the
normal operation mode.
FB
UG
LG
switching
・Short Circuit Protection with Timer Latch
REFIN/EN x 0.5
Short Circuit Protection kicks in when output falls to or
below REFIN/EN x 0.5. When the programmed time
period elapses, output is latched OFF to prevent
destruction of the IC. Output voltage can be restored
either by reconnecting the REFIN/EN pin (ON  OFF 
ON) or disabling UVLO (HIGH  Low  High).
FB
TSCP
SCP
REFIN/EN or UVLO
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7/20
2009.04 - Rev.B
Technical Note
BD95710MUV
●External Component Selection
1. Inductor (L) selection
The inductor value is a major influence on the output ripple
current. As formula (3) below indicates, the greater the inductor or
the switching frequency, the lower the ripple current.
ΔIL
(VIN-VOUT) x VOUT
[A]・・・(3)
L x VIN x f
The proper output ripple current setting is about 30% of maximum
output current.
ΔIL=
VIN
IL
ΔIL=0.3×IOUTmax/2. [A]・・・(4)
VOUT
L
L=
Co
(VIN-VOUT) x VOUT
ΔIL x VIN x f
[H]・・・(5)
(ΔIL: output ripple current; f: switch frequency)
Output Ripple Current
※Passing a current larger than the inductor’s rated current will cause magnetic saturation in the inductor and decrease
system efficiency. In selecting the inductor, be sure to allow enough margin to assure that peak current does not exceed the
inductor rated current value.
※To minimize possible inductor damage and maximize efficiency, choose a inductor with a low (DCR, ACR) resistance.
2. Output Capacitor (CO) Selection
At least 20mV ripple voltage of the FB voltage is recommended by taking the
equivalent series resistance and inductance into account.
VIN
Output ripple voltage is determined as in formula (6) below.
VOUT
L
ESR
ΔVOUT=ΔIL×ESR+ESL×ΔIL/TON・・・(6)
ESL
Co
Output Capacitor
(ΔIL: Output ripple current; ESR: CO equivalent series resistance,
ESL:equivalent series inductance)
※ In selecting a capacitor, make sure the capacitor rating allows sufficient
margin relative to output voltage. Note that a lower ESR can minimize output
ripple voltage.
Please give due consideration to the conditions in formula (7) below for output capacity, bearing in mind that output rise time
must be established within the soft start time frame.
Co≦
3msec×(Limit-IOUT/2)
VOUT
Limit: Current Limit Value
・・・(7)
Note: Improper capacitor may cause startup malfunctions.
3. Input Capacitor (Cin) Selection
The input capacitor selected must have low enough ESR resistance to fully
support large ripple output, in order to prevent extreme over current. The formula
for ripple current IRMS is given in (8) below.
VIN
Cin
VOUT
L
Co
IRMS=
IOUT
2
x
√VOUT(VIN-VOUT)
VIN
Where VIN=2×VOUT, IRMS=
[A]・・・(8)
IOUT
4
Input Capacitor
A low ESR capacitor is recommended to reduce ESR loss and maximize efficiency.
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8/20
2009.04 - Rev.B
Technical Note
BD95710MUV
4.MOSFET Selection
Pmain=PRON+PGATE+PTRAN
Loss on the main MOSFET
=
VOUT
4 x VIN
x RON x IOUT2 + Ciss x f x VDD+
2
VIN x Crss x IOUTx f
・・・(9)
2 x IDRIVE
(Ron: On-resistance of FET; Ciss: FET gate capacity;
f: switching frequency Crss: FET inverse transfer function;
IDRIVE: Gate peak current)
Loss on the synchronous MOSFET
Psyn=PRON+PGATE
=
VIN-VOUT
×RON×IOUT2+Ciss×f×VDD
・・・(10)
4 x VIN
5. OCP Setting Resistance
IOUT
VIN_BUS
VOUT
VIN_EXT
IL
L
r
L
RL
C
Co
r
r
RL
C
IIMAX =
Co
250kΩ
＋
VCSP2―VCSN2
・・・(11)
250kΩ
(VCSP1―VCS1-=IL× RL
, RL=
L
r×C
If VIMAX meet the following condition, OCP
becomes activated.
IMAX PIN
VIMAX≦IIMAX×RIMAX
RIMAX
(VIMAX: OCP Setting Voltage, VIMAX=1V)
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)
(RL: the DCR value of coil)
VIMAX
IIMAX
VCSP1―VCS1-
r
CSP1
CS1CSP2
CSN2
OCP
OCP threshold is determined by external OCP
setting resistance (RIMAX) and IMAX calculated
below.
9/20
2009.04 - Rev.B
Technical Note
BD95710MUV
6. Setting output voltage
The output voltage is REFIN/EN = VOUT when VOUT is tied to the FB directly. The range of VOUT is 0.4V ~ 3.3V.
VIN
BUSEN
R
H3RegTM
REFIN/EN
CONTROLLA
Q
VOUT
Driver
S
Circuit
FB
The output voltage is calculated as follow when resistor divider network is connected between the FB and VOUT.
REFIN/EN set 5Vcc.
Vout =
R1+R2
x 0.6 [V]・・・(12)
R2
VIN
BUSEN
0.6V
H3RegTM
R
CONTROLLA
S
Q
VOUT
Driver
Circuit
FB
R1
R2
7. Frequency Setting Resistance
The Frequency at steady state is determined by resistance value connected to RT pin.
But actual PHASE rising time and falling time are factored in due to the external MOSFET gate capacity or switching speed.
As a result, On-Time increases.
The frequency is determined by the following formula.
f [Hz]=
Ton =
VOUT
VIN
×
1
Ton
・・・(13)
-12
10 ×REFIN/EN×RRT
2×BUSEN
+ 170×10-9
Ton : ON TIME
Consequently, total frequency becomes lower than the formula above.
On-Time increases by Dead Time on the condition of zero cross point of inductor current. And also switching frequency
increases as the output current increases due to the fixed On-Time and the influence of conduction loss.
It is recommended that switching frequency be checked on large current condition (at the point where the inductor current
doesn’t become reversed from Vout).
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10/20
2009.04 - Rev.B
Technical Note
BD95710MUV
8. UVLO
BD95710MUV has function to detect input UVLO voltage in each VCC, 5VCC, and BUSEN for output voltage to start up.
If all these inputs go beyond their own UVLO threshold voltage, the soft start function kicks in.
These threshold voltages have their own hysteresis voltage to avoid faulty operation caused by input noises and glitchs.
Hysteresiwindow HysVCC
VCC
5VCC
Hys5VCC
BUSEN
HysBUSEN
VOUT
Tss
Output OFF
VCCUVLO
9. Current Phase Balance
Tss
Tss
Output OFF
Output OFF
5VCCUVLO
VCCUVLO
Tss
（Tss: Soft Start Time）
Output OFF
BUSENUVLO
Output OFF
VCCUVLO
VOUT
VIN_BUS
VIN_EXT
IL1
L1
RL1
r1
C1
IL2
Co
r1
ΔVcs2
CS1-
RL2
r2
C2
Co
r2
CSP1
ΔVcs1
L2
CSP2
CSN2
BD95710MUV keeps the current phase balance between coil current IL1 and IL2 by controlling the status ΔVcs1 = Δ
Vcs2.And for that, it is needed to meet the reference formula below.
L1 = L2 (RL1 =RL2), r1 = r2, C1 = C2. ・・・(14)
For detecting the value of ΔVcs1 or ΔVcs2 exactly, it is also needed to meet the formula below.
RL1 =
L1
r1×C1
・・・(15)
However, Vcs+ and Vcs- are fed a small current from current sense amplifier,
and this current causes a slight difference in the actual value obtained from
formula (15). Refer to formula (16) below:
PHA
⊿V
⊿Vcs=⊿V- I×r ・・・(16)
r
r2
I
⊿Vcs=(⊿V- I x r) + I x r2・・・(17)
I
To eliminate the difference, choose r2 to have the same value as r.
⊿Vcs
Vcs+
This difference can be compensated for by adding resistor r2.
Vcs-
www.rohm.com
© 2009 ROHM Co., Ltd. All rights reserved.
⊿Vcs=⊿V・・・(18)
11/20
2009.04 - Rev.B
Technical Note
BD95710MUV
10. Vout small Ripple Voltage
VIN
PHA
VOUT
R3
FB
R2
R1
C=56pF
Resistor R3 and capacitor C (=56pF)are needed to stabilize switching operation when Vout ripple voltage is less than
20mV. The values of R1, R2 and R3 are determined as in the formula (19) below
R1+R2 ≦ 20kΩ,10×R1 ≦ R3 ・・・(19)
www.rohm.com
© 2009 ROHM Co., Ltd. All rights reserved.
12/20
2009.04 - Rev.B
Technical Note
BD95710MUV
●Reference Data
VOUT
VOUT
VOUT
REFIN/
REFIN/
REFIN/
BUSEN
BUSEN
BUSEN
VCC
VCC
VCC
Fig1.Sequence
Fig3.Sequence
Fig2.Sequence
VOUT
VOUT
REFIN/
REFIN/
BUSEN
BUSEN
BUSEN
VCC
VCC
VCC
Fig4.Sequence
VOUT
REFIN/
Fig6.Sequence
Fig5.Sequence
VOUT(100mV/div)
VOUT(100mV/div)
VOUT(100mV/div)
HG1,HG2(10V/div）
HG1,HG2(10V/div）
HG1,HG2(10V/div）
IOUT
IOUT
(20A/div)
Fig7.Load Transient Response
(VCC=12V)
VOUT(100mV/div)
Fig8.Load Transient Response
(VCC=12V)
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© 2009 ROHM Co., Ltd. All rights reserved.
Fig9.Load Transient Response
(VCC=5V)
VOUT(100mV/div)
HG1,HG2(10V/div）
HG1,HG2(10V/div）
IOUT
(20A/div)
(20A/div)
Fig10.Load Transient Response
(VCC=5V)
(20A/div)
(20A/div)
VOUT(100mV/div)
HG1,HG2(10V/div）
IOUT
IOUT
Fig11.Load Transient Response
(VCC=8V)
13/20
IOUT
(20A/div)
Fig12.Load Transient Response
(VCC=8V)
2009.04 - Rev.B
Technical Note
BD95710MUV
●Reference Data
VOUT
VOUT
VOUT
PHASE1,
PHASE1,
PHASE1,
LGATE
LGATE
LGATE
Fig13.Continuos MODE
(VCC=5V)
Fig14.Continuos MODE
(VCC=8V)
Fig15.Continuos MODE
(VCC=12V)
VOUT
VOUT
VOUT
REFIN/
PHASE
PHASE
PHASE
IOUT
1msec
BUSEN
REFIN/
Fig16.SCP Function
Fig18.Soft Start
Fig17.SCP Function
REFIN/
f = 400kHz
390
100
8V DRIVE
90
370
80
PHASE1,
12V DRIVE
70
efficiency[%]
VOUT
f[kHz]
350
330
310
60
50
40
30
290
20
270
10
0
250
0
10
20
30
40
50
1
10
Iout[A]
Fig19.Reference Function
5V DRIVE
100
Iout[A]
Fig20.Frequency range functionally
Fig21.Efficiency
IL1, IL2
IL1, IL2
PHASE1,
Fig22.Current balance
(Io=20A)
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© 2009 ROHM Co., Ltd. All rights reserved.
IL1, IL2
PHASE1,
PHASE1,
Fig23.Current balance
(Io=30A)
14/20
Fig24.Current balance
(Io=40A)
2009.04 - Rev.B
Technical Note
BD95710MUV
■ BD95710MUV Evaluation Board Circuit with 5V Drive (VCC=5V input , VIN=3.3~12V input , REFIN/EN=5VCC,
Vout=1.2V )
VIN
U1
BD95710MUV_VQFN24
BUSEN
5
BUSEN
BOOT1
2
21
VCC
VCCDRV
C2
M3
M2
UGATE1 1
C5
PGND
22
VCC5
3
PHASE1
5VCC
LGATE1
PHASE1
56pF
M8
20
CSN2
8
PGND
7
R21
PGND
FB
REFOUT_POK
16
R18
C27
C17
C16
C15
PGND
PGND
PGND
L2
PGND
PGND
PGND
PGND
PGND
IOUT
CSN1
13
M9
LGATE2
PGND
14
C21
×２
RT
PGND
PGND
PHASE2 19
IOUT
10
PGND
PGND
PGND
AGND
RT
11
M7
PGND
C12
12
AGND
M6
UGATE2 18
C11
AGND
AGND
R15
17
C14
BOOT2
PGND
C13
REFIN/EN
C10
AGND
PGND
PGND
C19
4
R9
L1
100kΩ
AGND
R8
M5
VOUT
15
C18
M4
23
FB
CSP2
POK
CSP1
R16
R20
9
R17
6
HS
AGND
C24
REFIN/EN
PGND
24
C23
C7
PGND
×２
VCC
100kΩ
C25
C9
5V
C28
R3
C8
R2
C3
PGND
C31
3.3V ~ 12V
■BD95710MUV Evaluation Board Parts List
Part
No
U1
M2
M3
M4
M5
M6
M7
M8
M9
C2
C3
C5
C7
C8
C9
C10
C11
C12
C13
C14
C15
C16
Value
Company
Part name
10uF
1uF
1uF
10uF
10uF
10uF
10uF
10uF
820uF
820uF
820uF
-
ROHM
infineon
infineon
Infineon
Infineon
Infineon
Infineon
Infineon
infineon
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
SANYO
SANYO
SANYO
-
BD95710MUV
BSC119N03SG
BSC119N03SG
BSC032N03SG
BSC032N03SG
BSC119N03SG
BSC119N03SG
BSC032N03SG
BSC032N03SG
CT32X5R106K25A
CM05B105K16A
CM105B105K16A
CM316X5R106M06A
CM21B106M06A
CM21B106M06A
CM21B106M06A
CM21B106M06A
NC641-643
NC641-643
NC641-643
-
www.rohm.com
© 2009 ROHM Co., Ltd. All rights reserved.
Part
No
C17
C18
C19
C21
C23
C24
C25
C27
C28
C31
R2
R3
R8
R9
R15
R16
R17
R18
R20
R21
L1
L2
15/20
Value
Company
Part name
1uF
10uF
1uF
0.1uF
0.1uF
10uF
10uF
10uF
10uF
300kΩ
30kΩ
240kΩ
3.6MΩ
10kΩ
4.87kΩ
4.87kΩ
10kΩ
4.87kΩ
4.87kΩ
0.47uH
0.47uH
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
Cyntec
Cyntec
CM05B105K06A
CT32X5R106K25A
CM105B105K16A
CM105X5R224K25A
CM105X5R224K25A
CM316X5R106M10A
CM316X5R106M06A
CT32X5R106K25A
CT32X5R106K25A
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
PCMB105T-R47MS
PCMB105T-R47MS
2009.04 - Rev.B
Technical Note
BD95710MUV
■BD95710MUV Evaluation Board Circuit with 8V Drive (VIN=10.8~13.2V input , REFIN/EN=5VCC, Vout=1.2V )
BUSEN
PGND
5
U1
BD95710MUV_VQFN24
BUSEN
BOOT1
2
21
VCC
VCCDRV UGATE1
C2
M3
M2
1
C28
R3
C5
PGND
22
PGND
VCC5
3
LGATE1
PHASE1
CSN2
13
M9
C17
C16
C15
C14
C13
C21
M8
20
PGND
PGND
PGND
PGND
C12
C11
C10
C9
19
8
PGND
7
R21
FB
REFOUT_POK
16
R18
C27
AGND
PGND
CSN1
PGND
PGND
L2
PGND
PGND
PGND
PGND
PGND
IOUT
PGND
220pF
PGND
PGND
PGND
C8
PHASE2
RT
LGATE2
14
M7
AGND
IOUT
10
M6
18
PGND
RT
11
PGND
17
AGND
UGATE2
12
R15
PGND
100kΩ
4
AGND
R9
L1
C19
REFIN/EN
BOOT2
AGND
R8
23
M5
VOUT
15
AGND
C18
M4
FB
CSP2
POK
CSP1
R16
R20
9
R17
HS
AGND
6
C24
REFIN/EN
PHASE1
5VCC
24
C23
C7
PGND
VCC
100kΩ
C25
C31
C3
R1
3.3V ~ 12V
R２
VIN
■BD95710MUV Evaluation Board Parts List
Part
No
U1
M2
M3
M4
M5
M6
M7
M8
M9
C2
C3
C5
C7
C8
C9
C10
C11
C12
C13
C14
C15
C16
C17
Value
Company
Part name
10uF
1uF
1uF
10uF
10uF
10uF
10uF
10uF
820uF
820uF
820uF
-
ROHM
infineon
infineon
Infineon
Infineon
Infineon
Infineon
Infineon
infineon
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
SANYO
SANYO
SANYO
-
BD95710MUV
BSC119N03SG
BSC119N03SG
BSC032N03SG
BSC032N03SG
BSC119N03SG
BSC119N03SG
BSC032N03SG
BSC032N03SG
CT32X5R106K25A
CM05B105K16A
CM105B105K16A
CM316X5R106M06A
CM21B106M06A
CM21B106M06A
CM21B106M06A
CM21B106M06A
NC641-643
NC641-643
NC641-643
-
www.rohm.com
© 2009 ROHM Co., Ltd. All rights reserved.
Part
No
C18
C19
C21
C23
C24
C25
C27
C28
C31
R1
R2
R3
R8
R9
R15
R16
R17
R18
R20
R21
L1
L2
16/20
Value
Company
Part name
1uF
10uF
1uF
0.1uF
0.1uF
10uF
10uF
10uF
10uF
10kΩ
300kΩ
30kΩ
240kΩ
3.6MΩ
10kΩ
4.87kΩ
4.87kΩ
10kΩ
4.87kΩ
4.87kΩ
0.47uH
0.47uH
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
Cyntec
Cyntec
CM05B105K06A
CT32X5R106K25A
CM105B105K16A
CM105X5R224K25A
CM105X5R224K25A
CM316X5R106M10A
CM316X5R106M06A
CT32X5R106K25A
CT32X5R106K25A
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
PCMB105T-R47MS
PCMB105T-R47MS
2009.04 - Rev.B
Technical Note
BD95710MUV
■BD95710MUV Evaluation Board Circuit with 12V Drive ( VIN=12V input, VCC=8V input, REFIN/EN=5VCC, Vout=1.2V )
VIN
U1
BD95710MUV_VQFN24
BUSEN
5
BUSEN
BOOT1
2
21
VCC
VCCDRV UGATE1
C2
M3
M2
1
C28
R3
C5
PGND
22
VCC5
3
PHASE1
5VCC
LGATE1
PHASE1
PHASE2
RT
LGATE2
CSN2
220pF
PGND
CSN1
M8
M9
8
PGND
7
R21
FB
13
C17
C16
C15
PGND
PGND
C12
19
20
PGND
L2
PGND
PGND
PGND
PGND
PGND
IOUT
PGND
14
PGND
PGND
AGND
IOUT
10
PGND
PGND
PGND
PGND
RT
11
M7
C8
12
M6
18
C11
UGATE2
C10
AGND
C13
PGND
17
AGND
AGND
PGND
PGND
C31
BOOT2
4
R9
L1
C19
REFIN/EN
AGND
R8
M5
VOUT
15
C18
M4
23
C21
REFIN/EN
PGND
24
100kΩ
C7
PGND
VCC
100kΩ
C25
C14
R2
C3
PGND
C9
12V
FB
CSP2
POK
CSP1
R16
R20
9
R15
HS
AGND
C24
AGND
R17
6
C23
REFOUT_POK
16
R18
C27
■BD95710MUV Evaluation Board Parts List
Part
No
U1
M2
M3
M4
M5
M6
M7
M8
M9
C2
C3
C5
C7
C8
C9
C10
C11
C12
C13
C14
C15
C16
Value
Company
Part name
10uF
1uF
1uF
10uF
10uF
10uF
10uF
10uF
820uF
820uF
820uF
-
ROHM
infineon
infineon
Infineon
Infineon
Infineon
Infineon
Infineon
infineon
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
SANYO
SANYO
SANYO
-
BD95710MUV
BSC119N03SG
BSC119N03SG
BSC032N03SG
BSC032N03SG
BSC119N03SG
BSC119N03SG
BSC032N03SG
BSC032N03SG
CT32X5R106K25A
CM05B105K16A
CM105B105K16A
CM316X5R106M06A
CM21B106M06A
CM21B106M06A
CM21B106M06A
CM21B106M06A
NC641-643
NC641-643
NC641-643
-
www.rohm.com
© 2009 ROHM Co., Ltd. All rights reserved.
Part
No
C17
C18
C19
C21
C23
C24
C25
C27
C28
C31
R2
R3
R8
R9
R15
R16
R17
R18
R20
R21
L1
L2
17/20
Value
Company
Part name
1uF
10uF
1uF
0.1uF
0.1uF
10uF
10uF
10uF
10uF
300kΩ
30kΩ
240kΩ
3.6MΩ
10kΩ
4.87kΩ
4.87kΩ
10kΩ
4.87kΩ
4.87kΩ
0.47uH
0.47uH
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
KYOCERA
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
ROHM
Cyntec
Cyntec
CM05B105K06A
CT32X5R106K25A
CM105B105K16A
CM105X5R224K25A
CM105X5R224K25A
CM316X5R106M10A
CM316X5R106M06A
CT32X5R106K25A
CT32X5R106K25A
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
MCR03
PCMB105T-R47MS
PCMB105T-R47MS
2009.04 - Rev.B
Technical Note
BD95710MUV
●Operation Notes
1. Absolute maximum ratings
An excess in the absolute maximum ratings, such as supply voltage, temperature range of operating conditions, etc., can
break down the devices, thus making impossible to identify breaking mode, such as a short circuit or an open circuit. If any
over rated values wll expect to exceed the absolute maximum ratings, consider adding circuit protection devices, such as
fuses.
2. Connecting the power supply connector backward
Connecting of the power supply in reverse polarity can damage IC. Take precautions when connecting the power supply
lines. An external direction diode can be added.
3. Power supply lines
Design PCB layout pattern to provide low impedance GND and supply lines. To obtain a low noise ground and supply line,
separate the ground section and supply lines of the digital and analog blocks. Furthermore, for all power supply terminals
to ICs, connect a capacitor between the power supply and the GND terminal. When applying electrolytic capacitors in the
circuit, not that capacitance characteristic values are reduced at low temperatures.
4. GND voltage
The potential of GND pin must be minimum potential in all operating conditions.
5. Thermal design
Use a thermal design that allows for a sufficient margin in light of the power dissipation (Pd) in actual operating conditions.
6. Inter-pin shorts and mounting errors
Use caution when positioning the IC for mounting on printed circuit boards. The IC may be damaged if there is any
connection error or if pins are shorted together.
7. Actions in strong electromagnetic field
Use caution when using the IC in the presence of a strong electromagnetic field as doing so may cause the IC to
malfunction.
8. ASO
When using the IC, set the output transistor so that it does not exceed absolute maximum ratings or ASO.
9. Thermal shutdown circuit
The IC incorporates a built-in thermal shutdown circuit (TSD circuit). The thermal shutdown circuit (TSD circuit) is designed
only to shut the IC off to prevent thermal runaway. It is not designed to protect the IC or guarantee its operation. Do not
continue to use the IC after operating this circuit or use the IC in an environment where the operation of this circuit is
assumed.
BD95710MUV
TSD on temperature [°C] (typ.)
175
Hysteresis temperature [°C] (typ.)
15
10. Testing on application boards
When testing the IC on an application board, connecting a capacitor to a pin with low impedance subjects the IC to stress.
Always discharge capacitors after each process or step. Always turn the IC's power supply off before connecting it to or
removing it from a jig or fixture during the inspection process. Ground the IC during assembly steps as an antistatic
measure. Use similar precaution when transporting or storing the IC.
www.rohm.com
© 2009 ROHM Co., Ltd. All rights reserved.
18/20
2009.04 - Rev.B
Technical Note
BD95710MUV
11. Regarding 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 these Payers w the N layers of other elements, creating a parasitic diode or
transistor. For example, the relation between each potential is as follows:
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 can occur inevitable in the structure of the IC. The operation of parasitic diodes can result in mutual
interference among circuits, operational faults, or physical damage. Accordingly, methods by which parasitic diodes
operate, such as applying a voltage that is lower than the GND (P substrate) voltage to an input pin, should not be used.
Resistor
Transistor (NPN)
Pin A
Pin B
C
Pin B
B
E
Pin A
P+
N
N
P+
P
N
N
P substrate
Parasitic element
Parasitic
element
GND
P+
B
N
P+
P
N
C
E
P substrate
Parasitic element
GND
GND
GND
Parasitic
element
Other adjacent elements
12. Ground Wiring Pattern
When using both small signal and large current GND patterns, it is recommended to isolate the two ground patterns,
placing a single ground point at the ground potential of application so that the pattern wiring resistance and voltage
variations caused by large currents do not cause variations in the small signal ground voltage. Be careful not to change the
GND wiring pattern of any external components, either.
●Power Dissipation
Power dissipation:Pd [W]
4.0
2
4 layers (Copper foil area : 5505mm )
copper foil in each layers.
θj-a=35.1℃/W
2
② 4 layers (Copper foil area : 10.29m )
copper foil in each layers.
θj-a=103.3℃/W
2
③ 4 layers (Copper foil area : 10.29m )
θj-a=178.6℃/W
④IC only.
θj-a=367.6℃/W
①
①3.56W
3.0
2.0
②1.21W
1.0
③0.70W
④0.34W
0
0
25
50
75
100105 125
150
Ambient temperature:Ta [℃]
Fig.25 Thermal derating curve
(VQFN020V4040)
www.rohm.com
© 2009 ROHM Co., Ltd. All rights reserved.
19/20
2009.04 - Rev.B
Technical Note
BD95710MUV
●Type Designations (Selections) for Ordering
B
D
9
Part No.
5
7
1
0
M
Part No.
U
V
-
Package
MUV : VQFN024V4040
E
2
Packaging and forming specification
E2: Embossed tape and reel
VQFN024V4040
<Tape and Reel information>
4.0±0.1
4.0±0.1
1.0MAX
2.4±0.1
0.4±0.1
7
12
19
18
0.5
The direction is the 1pin of product is at the upper left when you hold
( reel on the left hand and you pull out the tape on the right hand
)
6
24
0.75
E2
2.4±0.1
1
2500pcs
(0.22)
+0.03
0.02 -0.02
S
C0.2
Embossed carrier tape
Quantity
Direction
of feed
1PIN MARK
0.08 S
Tape
13
+0.05
0.25 -0.04
1pin
(Unit : mm)
www.rohm.com
© 2009 ROHM Co., Ltd. All rights reserved.
Reel
20/20
Direction of feed
∗ Order quantity needs to be multiple of the minimum quantity.
2009.04 - Rev.B
Notice
Notes
No copying or reproduction of this document, in part or in whole, is permitted without the
consent of ROHM Co.,Ltd.
The content specified herein is subject to change for improvement without notice.
The content specified herein is for the purpose of introducing ROHM's products (hereinafter
"Products"). If you wish to use any such Product, please be sure to refer to the specifications,
which can be obtained from ROHM upon request.
Examples of application circuits, circuit constants and any other information contained herein
illustrate the standard usage and operations of the Products. The peripheral conditions must
be taken into account when designing circuits for mass production.
Great care was taken in ensuring the accuracy of the information specified in this document.
However, should you incur any damage arising from any inaccuracy or misprint of such
information, ROHM shall bear no responsibility for such damage.
The technical information specified herein is intended only to show the typical functions of and
examples of application circuits for the Products. ROHM does not grant you, explicitly or
implicitly, any license to use or exercise intellectual property or other rights held by ROHM and
other parties. ROHM shall bear no responsibility whatsoever for any dispute arising from the
use of such technical information.
The Products specified in this document are intended to be used with general-use electronic
equipment or devices (such as audio visual equipment, office-automation equipment, communication devices, electronic appliances and amusement devices).
The Products specified in this document are not designed to be radiation tolerant.
While ROHM always makes efforts to enhance the quality and reliability of its Products, a
Product may fail or malfunction for a variety of reasons.
Please be sure to implement in your equipment using the Products safety measures to guard
against the possibility of physical injury, fire or any other damage caused in the event of the
failure of any Product, such as derating, redundancy, fire control and fail-safe designs. ROHM
shall bear no responsibility whatsoever for your use of any Product outside of the prescribed
scope or not in accordance with the instruction manual.
The Products are not designed or manufactured to be used with any equipment, device or
system which requires an extremely high level of reliability the failure or malfunction of which
may result in a direct threat to human life or create a risk of human injury (such as a medical
instrument, transportation equipment, aerospace machinery, nuclear-reactor controller,
fuel-controller or other safety device). ROHM shall bear no responsibility in any way for use of
any of the Products for the above special purposes. If a Product is intended to be used for any
such special purpose, please contact a ROHM sales representative before purchasing.
If you intend to export or ship overseas any Product or technology specified herein that may
be controlled under the Foreign Exchange and the Foreign Trade Law, you will be required to
obtain a license or permit under the Law.
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More detail product informations and catalogs are available, please contact us.
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