Regulators ICs for Digital Cameras and Camcorders
Switching Regulator IC
with Built-in FET (5V)
No.10036EAT09
BD9757MWV
●Description
BD9757MWV is an 8-channel switching regulator with a built-in FET for digital still camera. It has a built-in function to
light-control the white LED for backlight according to the light control setting signal from microcomputer.
●Features
1) Starting from VBAT terminal of 1.5V
2) Power of internal circuit is supplied from voltage boost CH1
3) Mounted with a total of 8ch including voltage boost 2ch, voltage step-down 4ch, inversion 1ch, and white
LED-purpose voltage boost (compatible with DC light control) 1ch
4) Built-in 5-channel transistors for synchronous rectification
5) Built-in 2-channel FET transistors for voltage boost
6) Built-in all-channel phase compensation between input and output of error amplifier
7) Channel 1 and 3 are common, but other channels are independent, so the ON/OFF is possible
8) Operating frequencies of 1.2MHz (CH1 ~ 5), 600KHz(CH6 ~ 8)
9) Built-in output breaking circuit (timer latch type) at the time of overload
10) Built-in 2ch of high side switch with soft start function
11) UQFN044V6060 package (6mm×6mm ,0.4mm pitch) with heat dissipation
●Applications
Digital still camera
●Absolute maximum ratings (Ta=25℃)
Parameter
Symbol
Ratings
Units
VBAT
-0.3 ~ 7
V
VHx1 ~ 5
-0.3 ~ 7
V
HS78H
-0.3 ~ 7
V
VLx7,8
-0.3 ~ 22
V
IomaxLx1
±2.5
A
IomaxHx1
±1.5
A
IomaxHx2,5
+1.0
A
IomaxHx3,4
+0.8
A
IomaxHS78
+1.2
A
IomaxLx7,8
±1.0
A
Pd
0.54(※1)
W
Operating temperature range
Topr
-25 ~ +85
℃
Storage temperature range
Tstg
-55 ~ +150
℃
Tjmax
+150
℃
Power Supply Voltage
Power Input Voltage
Maximum output current
Power Dissipation
Junction temperature
※1 At the time of a single IC. If used in more than Ta=25℃, reduced by 4.32mW/℃.
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1/20
2010.11 - Rev.A
Technical Note
BD9757MWV
●Operating conditions
Ratings
Parameter
Power supply voltage
VREF terminal connection capacity
VREGA terminal connection capacity
Symbol
Unit
Min.
Typ.
Max.
VBAT
1.5
-
5.5
V
CVREF
0.47
1.0
4.7
μF
CVREGA
0.47
1.0
4.7
μF
-
-
sec
-
-
sec
conditions
【CH8 modulated light】
H fixed time when the modulated
light control setting is determined
TON
L fixed time when OFF
TOFF
H fixed time at the time of
modulated light control setting
L fixed time at the time of
modulated light control setting
H fixed time at the time of EN starting up
L fixed time
before modulated light control setting
Time of light control setting
at the time of starting up
265X
1/fosc1
256X
1/fosc1
TH
500
-
10000
nsec
TL
500
-
10000
nsec
-
-
sec
TEN
TCLR
4X
1/fosc1
7X
1/fosc1
-
255X
1/fosc1
2048X
1/fosc1
sec
TSET
-
-
CH1 PMOS drain current
Idpl1
-
-
1.2
A
CH1 NMOS drain current
Idnl1
-
-
2.3
A
CH2,5 PMOS drain current
Idpl2
-
-
0.8
A
CH2, 5 NMOS drain current
Idnl2
-
-
0.8
A
CH3, 4 PMOS drain current
Idpl22
-
-
0.6
A
CH3, 4 NMOS drain current
Idnl22
-
-
0.6
A
CH6 driver output peak current
Idpeak
-
-
±0.5
A
CH7, 8 high side switch input current
Idpl7,8
-
-
1.0
A
Idnl6
-
-
0.8
A
CH1
-
4.5
-
5.4
V
CH2
-
1.0
-
4.4
V
CH3
-
1.0
-
4.4
V
CH4
-
1.0
-
4.4
V
CH5
-
1.0
-
4.4
V
CH6
-
-8.0
-
-5.0
V
CH7
-
8.5
-
16
V
CH8
-
8.5
-
20
V
sec
【Driver】
CH7, 8 NMOS drain current
【Output voltage setting range】
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2/20
2010.11 - Rev.A
Technical Note
BD9757MWV
●Electrical characteristics (Unless specified, Ta=25℃, VCCOUT=5.0V, VBAT=3V, STB13 ~ 7=3V,UPIC8=2.5V)
Limits
Parameter
Symbol
Unit
Conditions
Min.
Typ.
Max.
2.4
2.5
2.6
V
Io=5mA
VREGA monitor
【Internal regulator VREGA】
Output voltage
VREGA
【Low-voltage input malfunction prevention circuit】
Detecting voltage 1
Vstd1
-
2.0
2.3
V
Hysteresis width 1
⊿Vstd1
50
100
200
mV
Detecting voltage 2
Vstd2
-
2.4
2.5
V
Hysteresis width 2
⊿Vstd2
100
200
300
mV
Tscp
20
25
30
msec
Vtcinv
0.38
0. 48
0.58
V
Oscillating frequency
Fstart
150
300
600
kHz
Operation initiation VBAT voltage
Vst1
1.5
-
-
V
Start-up CH soft start time
Tss1
1.8
3.0
5.3
msec
Oscillating frequency CH1 ~ 5
fosc1
1.0
1.2
1.4
MHz
Oscillating frequency CH6 ~ 8
fosc2
0.5
0.6
0.7
MHz
Max duty 2,3,4,5(voltage step-down)
Dmax1d
-
-
100
%
Max duty 1(voltage boost)
Dmax1u
86
92
96
%
Max duty 6,7,8
Dmax2
86
92
96
%
IINV
-
0
50
nA
INV1 ~ 8, NON5=3.0V
INV threshold 1
VINV1
0.79
0.80
0.81
V
CH1 ~ 5
INV threshold 2
VINV2
0.99
1.00
1.01
V
CH7,8V
VINV3
370
400
430
mV
VOUT6
-6.09
-6.00
-5.91
V
NON6 12kΩ, 72kΩ(※3)
DVLi
-
4.0
12.5
mV
VCCOUT=1.5 ~ 5.5V
Ios
0.2
1.0
-
mA
Vref=0V
CH2, 5 soft start time
Tss2, 5
3.4
4.4
5.4
msec
CH3, 4 soft start time
Tss3, 4
1.2
2.2
3.2
msec
Tss6
3.4
4.4
5.4
msec
Tss7, 8
4.4
5.4
6.6
msec
VCCOUT monitor
【Short-circuit protection circuit】
SCP detecting time
Timer start threshold voltage
INV terminal monitor
CH3 ~ 5
【Start circuit】
【Oscillating circuit】
(※2)
【Error AMP】
Input bias current
INV threshold 3
(max)
CH8I
【Base Bias Voltage Vref for inverted Channel】
CH6 output voltage
Line regulation
Output circuit at the time of short-circuit
【Soft start】
CH6 soft start time
CH7, 8 soft start time
※2
※3
◎
The protective circuit start working when circuit is operated by 100% duty.
So it is possible to use only for transition time shorter than charge time for SCP.
Recommend resistor value over 20kΩ between VREF to NON6, because VREF current is under 100µA.
This product is not designed for normal operation within a radioactive environment.
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3/20
2010.11 - Rev.A
Technical Note
BD9757MWV
●Electrical characteristics (Unless specified, Ta=25℃, VCCOUT=5.0V, VBAT=3V, STB13 ~ 7=3V,UPIC8=2.5V)
Limits
Parameter
Symbol
Unit
Min.
Typ.
Max.
Conditions
【Output Driver】
CH1 High side switch ON resistance
RON1p
-
120
270
mΩ
Hx1=5V
CH1 Low side switch ON resistance
RON1N
-
80
240
mΩ
VCCOUT=5.0V
CH2 High side switch ON resistance
RON21p
-
250
400
mΩ
Hx2=5V
CH2 Low side switch ON resistance
RON21N
-
250
400
mΩ
VCCOUT=5.0V
CH3 High side switch ON resistance
RON3p
-
250
400
mΩ
Hx3=3V ,
VCCOUT=5V
CH3 Low side switch ON resistance
RON3N
-
250
400
mΩ
VCCOUT=5.0V
CH4 High side switch ON resistance
RON4p
-
250
400
mΩ
Hx4=3V,
VCCOUT=5V
CH4 Low side switch ON resistance
RON4N
-
250
400
mΩ
VCCOUT=5.0V
CH5 High side switch ON resistance
RON5p
-
250
400
mΩ
Hx5=5V
CH5 Low side switch ON resistance
RON5N
-
150
300
mΩ
VCCOUT=5.0V
Output voltage H at the time of CH6 driving
Vout6H
-
V
Output voltage L at the time of CH6 driving
Vout6L
-
0.5
1.0
V
CH7,8 NMOS switch ON resistance
RON7,8N
-
500
800
mΩ
VCCOUT=5.0V
CH7,8 load switch ON resistance
RON7,8p
-
200
350
mΩ
HS7,8H=3V ,
VCCOUT=5.0V
operating
VSTBH1
1.5
-
5.5
V
Non-operating
VSTBL1
-0.3
-
0.3
V
RSTB1
250
400
700
kΩ
H level
VUPIH
2.1
-
4.00
V
L level
VUPIL
0
-
0.40
V
RUPIC1
30
50
80
kΩ
ISTB1
-
-
5
μA
ISTB4
-
-
5
μA
ISTB2
-
-
5
μA
Voltage step-down
ISTB3
-
-
5
μA
Voltage boost
IST
-
150
450
μA
VBAT=1.5V
Icc1
-
45
150
μA
VBAT=3.0V
Icc2
-
5.0
9.7
mA
INV1 ~ 8=1.2V ,
NON6=-0.2V
VCCOUT VCCOUT
-1.5
-1.0
IOUT6=50mA
NON6=0.2V
IOUT6=-50mA,
NON6=-0.2V
【STB1 ~ 7】
STB control voltage
Pull down resistance
【UPIC8】
UPIC8
Control voltage
Pull down resistance
【Circuit current】
VBAT terminal
Circuit current at the HS7,8H terminal
time of standby
Hx terminal
Lx terminal
Circuit current at the time of Start-up
(VBAT terminal inflow current)
Circuit current 1 at the time of operating
(VBAT terminal inflow current)
Circuit current 2 at the time of operating
(VCCOUT applied terminal inflow current)
◎
This product is not designed for normal operation within a radioactive environment.
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4/20
2010.11 - Rev.A
Technical Note
BD9757MWV
●Reference data (1)
Start-up circuit operating frequency temperature characteristic
Current mode operating frequency temperature characteristic
600
1.40
700
1.35
680
500
Voltage mode operating frequency temperature characteristic
660
1.30
200
freq[KHz]
300
640
1.25
freq[MHz]
freq[KHz]
400
1.20
1.15
520
1.00
-40
-20
0
20
40
60
80
100
500
-40
-20
0
20
40
Ta [℃]
Ta [℃]
60
80
100
-40
Fig.2 Frequency CH1 ~ 5-Temp
Fig.1 Start-up circuit frequency-Temp
580
540
1.05
0
600
560
1.10
100
620
VREGA output voltage temperature characteristic
-20
0
20
40
Ta [℃]
60
80
100
Fig.3 Frequency CH6 ~ 8-Temp
VREF6 output voltage temperature characteristic
2.60
1.06
2.58
2.56
1.04
2.52
2.50
2.48
VREF6 [V]
VREGA [V]
2.54
2.46
2.44
2.42
1.02
1.00
0.98
0.96
2.40
-40
-20
0
20
40
Ta [℃]
60
80
0.94
100
-40
Fig.4 VREGA output voltage-Temp
-20
0
20
40
Ta [℃]
60
80
100
Fig.5 CH6 Base voltage-Temp
CH1 boost 5.0 efficiency data
CH2 step-down 3.2V efficiency data
CH3 step-down 1.2V efficiency data
100
100
100
95
95
95
90
90
85
90
80
Vin=1.5V
75
Vin=2.4V
70
75
55
60
Vin=1.5V
60
55
Vin=2.4V
Vin=4.8V
50
Vin=4.2V
Vin=5.5V
45
40
50
10
100
1000
10000
10
100
100
0
Vin=3.6V
Vin=5.5V
10
100
1000
Load current[mA]
Load current[mA]
Load current [mA]
Fig.6 CH1
5.0V voltage boost efficiency-Io
Fig.7 CH2
3.2V step-down efficiency-Io
Fig.8 CH2
3.2V step-down efficiency-Io
CH4 step-down 1.8V efficiency data
CH6 Reversal -6V efficiency data
CH5 step-down 3.5V efficiency data
100
95
95
90
85
90
100
90
Efficiency [%]
100
85
80
Efficiency [%]
Efficiency [%]
65
Vin=3.6V
60
Vin=4.2V
75
70
Vin=4.2V
70
65
Vin=3.6V
65
80
80
Efficiency
85
Efficiency
Efficiency
85
75
70
65
80
75
70
60
Vin=2.4V
55
50
Vin=3.6V
Vin=4.2V
60
45
Vin=5.5V
55
Vin=4.2V
65
10
100
1000
Load current [mA]
Fig.9 CH4
1.8V step-down efficiency-Io
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70
Vin=2.4V
Vin=3.6V
60
Vin=4.2V
Vin=4.8V
Vin=5.5V
50
Vin=5.5V
40
50
40
80
10
100
1000
Load current [mA]
Fig.10 CH5
3.5V step-down efficiency-Io
5/20
1
10
100
Load current [mA]
Fig.11 CH6
-6V inverting efficiency-Io
2010.11 - Rev.A
Technical Note
BD9757MWV
●Reference data (2)
CH8 LED efficiency data
CH7 boost12V efficiency data
100
100
90
95
Efficiency [V]
Efficiency [%]
Io=7.5mA
80
70
Vin=1.5V
60
Vin=2.4V
Io=12.5mA
Io=17mA
90
Io=20mA
85
80
Vin=3.6V
50
75
Vin=4.2V
Vin=5.5V
70
40
1
10
100
0
1
Fig.12 CH7 12V boost efficiency-Io
2
3
4
5
6
Input voltaage [V]
Load current [mA]
Fig.13 CH8 LED boost efficiency-Io
STB13
STB2
STB13
Vo1
Vo1
Vo2
Vo3
Inflow current(1A/Div)
Inflow current (1A/Div)
Inflow current (1A/Div)
Fig.14 CH1 start-up waveform
(VBAT=1.5V)
STB4
Fig.15 CH1,3 start-up waveform
(VBAT=3.0V)
Fig.16 CH2 start-up waveform
STB6
STB5
Vo6
Vo4
Vo5
Inflow current (1A/Div)
Fig.17 CH4 start-up waveform
STB7
Inflow current(1A/Div)
Fig.18 CH5 start-up waveform
Inflow current (1A/Div)
Fig.19 CH6 start-up waveform
UPIC8
Vo7
Vo8
Inflow current (1A/Div)
Inflow current (1A/Div)
Fig.20 CH7 start-up waveform
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Fig.21 CH8 start-up waveform
6/20
2010.11 - Rev.A
Technical Note
BD9757MWV
35
HS7L
36
HS78H
37
HS8L
38
39
LX8
PGND678
40
41
INV3
INV4
VBAT
HX1
HX1
21
19
LX1
18
LX1
17
LX7
PGND13
16
OUT6
UPIC8
PGND13
LX3
15
14
HX3
13
4
5
6
7
8
STB4
3
STB2
LX2
2
HX4
HX2
1
PGND24
LX4
HX5
STB7
STB6
BD9757MWV
LX5
44
22
PGND5
43
24 23
INV1
STB5
42
25
INV2
NON6
INV8
27 26
GND
INV7
34
28
VCCOUT
VREGA
31 30 29
INV5
32
VREF6
33
INV8I
●Pin Assignment
9
10
11
20
STB13 12
Fig.22 BD9757MWV Top VIEW
●Pin Description
PIN No.
PIN name
I/O
21
VBAT
I
Battery voltage input
28
VCCOUT
I
Power supply input terminal
26
GND
-
Earth terminal
PGND13,24,5, 678
-
Earth terminal with built-in FET
27
VREGA
O
VREGA output
2.5V output
30
VREF6
O
reference voltage output for CH6 inversion
1.0V output
41
OUT6
O
CH6 PMOS gate connection terminal
Hx1,2,3,4,5
O
Synchronous rectification high side switch
input terminal, Pch Driver power supply output
Lx1,,2,3,4,5,7,8
O
Inductor connection terminal
HS78H
I
Built-in load switch power supply input
terminal
HS7L,HS8L
O
Built-in load switch output terminal
INV1,2,3,4,5,7,8
I
Error amplifier inversion input terminal
31
NON6
I
Error amplifier non-inversion input terminal
33
INV8I
I
Error amplifier inversion input terminal
STB13,2,4,5,6,7
I
UPIC8
I
15,16,7,2,39
19,20,5,13,9,4
17,18,6,14,8,3,40,38
36
35,37
22,25,23,24,29,32,34
12,10,11,1,44,43
42
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© 2010 ROHM Co., Ltd. All rights reserved.
Function
CH1 ~ CH7 ON / OFF switch
Operating :higher than 1.5V
CH8 start-up signal, LED light
control-purpose signal input
7/20
Notes
Starting up at
higher than 1.5V
Connecting
the CH1 output
At the time of All Low
Standby state
2010.11 - Rev.A
Technical Note
BD9757MWV
●Application circuit (1)
Fig.23 Applied circuit diagram 1(lithium 1 cell)
○Operation notes
・we are confident that
the above applied circuit diagram should be recommended, but please thoroughly confirm its characteristics when using it. In
addition, when using it with the external circuit’s constant changed, please make a decision that allows a sufficient margin in light of the fluctuations of
external components and ROHM’s IC in terms of not only static characteristic but also transient characteristic.
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8/20
2010.11 - Rev.A
Technical Note
BD9757MWV
●Application circuit (2)
Fig.24 Applied circuit diagram 2(dry battery ×2)
○Operation notes
・we are confident that
the above applied circuit diagram should be recommended, but please thoroughly confirm its characteristics when using it. In
addition, when using it with the external circuit’s constant changed, please make a decision that allows a sufficient margin in light of the fluctuations of
external components and ROHM’s IC in terms of not only static characteristic but also transient characteristic.
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9/20
2010.11 - Rev.A
Technical Note
BD9757MWV
●Timing chart (1)
STB13,
STB2
Tss1
After finished CH1 rise,
other CH start rise.
CH1
Tss1 About 3.0msec
Tss3
Tss3 About 2.2msec
CH3
Tss2
Tss2 About 4.4msec
CH2
STB4, STB5
When CH1 is already risen,
CH is start up with STB rise.
Tss4
Tss4 About 2.2msec
CH4
Tss5
Tss5 About 4.4msec
CH5
Fig.25 CH1 ~ 5 start-up sequence
STB6, STB7
CH6
reverse output
Tss6
Tss6 About4.4msec
Tss7
CH7
output
Tss7 About5.4msec
Fig.26 CH6, 7 start-up sequence
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10/20
2010.11 - Rev.A
Technical Note
BD9757MWV
●Timing chart (2)
Interval of modulated light setting
UPIC8
About 5.4msec
Soft start is started
Tss8
according to setting
Tss8
Oscillating frequency=6400counts
about 5.4msec
LED current
LED current is adjusted according to the set number of counts
Interval of soft start
It is returned immediately if the set voltage is exceeded
Vo8
Fig.27 CH8 start-up sequence
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11/20
2010.11 - Rev.A
Technical Note
BD9757MWV
●Block explanation
1.
VREGA
It is a regulator with output voltage of 2.5V and used as a power supply of internal block. In addition, it outputs to
outside from VREGA terminal (32pin). 1.0μF is recommended as an external capacitor for oscillation prevention.
2.
SCP, Timer Latch
It is a timer latch type of short-circuit protection circuit.
For CH1,2, 6 ~ 8, the error AMP output voltage is monitored, and detected when the feedback voltage deviates from
control, for CH3 ~ 5, it is detected when the voltage of INV terminal becomes lower than 80%, and in 25ms the latch
circuit operates and the outputs of all the channels are fixed at OFF.
In order to reset the latch circuit, please turn off all the STB terminals before turning them on once again or turning
power supply on once again.
3.
U.V.L.O (Under Voltage Lockout)
It is a circuit to prevent malfunction at low voltage.
It is to prevent malfunction of internal circuit at the time of rising or dropping to a lower value of power supply voltage.
If the voltage of VCCOUT terminal becomes lower than 2.4V, then the output of each DC/DC converter is reset to OFF,
and SCP’s timer latch & soft start circuit are reset. When control is deviated from, the operation of CH1 at the time of
start-up will be explained in START UP OSC mentioned later.
4.
Voltage Reference (VREF6)
For the reference voltage circuit of CH6 inversion CH, the output voltage is 1V and outputted from VREF6 terminal
(30pin). According this voltage and the output voltage of CH6, the dividing resistance (resistor) is set and then the
output voltage is set. If STB6 terminal is made to be H level at the time of start-up, then increase gradually the voltage
up to 1V. The inversion output of CH6 follows this voltage and performs the soft start. 1.0μF is recommended as the
external capacitor.
5.
OSC
It is an oscillation circuit the frequency of which is fixed by a built-in CR.
The operating frequencies of CH1 ~ CH5 are set at 1.2MHz, and the operating frequencies of CH6 ~ CH8 are set at
600kHz.
6.
ERRAMP 1 ~ 8
It is an error amplifier to detect output signal and output PWM control signal. The reference voltages of ERRAMP
(Error Amplifier) of CH1, 2,3,4,5 are internally set at 0.8V, and the reference voltages of ERRAMP (Error Amplifier) of
CH7.8 are set at 1.0V. The reference voltage of CH6 is set at GND potential, and for CH8’s ERRAMP81, the maximum
value of the reference voltage is set at 0.4V. In addition, each CH incorporates a built-in element for phase
compensation.
7.
ERRCOMP , Start Up OSC
It is a comparator to detect the output voltage and control the start circuit, and also an oscillator that is turned ON/OFF
by this comparator and starts operating from 1.5V. The frequency of this oscillator is about 300 kHz fixed internally. This
oscillator stops operating if VCC terminal becomes more than 2.6V or the soft start time is exceeded.
8.
Current mode control block
CH1 ~ 5 adopt the PWM method based on current mode.
For a current- mode DC/DC converter, FET at the main side of synchronous rectification is turned on when detecting
the CLK’s edge, and turned off by detecting the peak current by means of the current comparator.
9.
PWM COMP
PWM converter is a voltage-pulse width converter to control output voltage according to input voltage. It compares the
output voltage of error amplifier with the SLOPE waveform, controls the pulse width and outputs to driver. The driver is
turned on during the output of error amplifier being higher than SLOPE waveform. The maximum ON duty is set at
about 92% internally.
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12/20
2010.11 - Rev.A
Technical Note
BD9757MWV
10. Nch DRIVER , Pch DRIVER
It is a CMOS inverter type of output circuit to drive both built-in and external Nch,Pch FET.
11. Load switch
It is a circuit, mounted in CH7, 8, to control the Load switch. HS78H terminal (36pin) is input terminal, and the HS67
and HS78 terminals (40,37pin) are output terminals.
This control circuit can prevent the rush current at the time of switch ON because the soft start starts functioning at the
time of start-up. In addition, this Load switch is provided with OCP function to prevent the IC from damage.
Ensure that the IC is used within Load switch’s rated current when used normally.
12. ON/OFF LOGIC
It is the voltage applied to STB terminal and can control the ON/OFF of CH1 ~ CH7.
If the voltage more than 1.5V is applied, then it becomes ON, but if open or 0V is applied, then it becomes off,
furthermore, it all the channels are turned off, then the whole IC will be in standby state. In addition, STB13 ~ STB7
terminals contain respectively a built-in pull-down resistor of about 400kΩ. UPIC8 is the input terminal of the start signal
and the light control signal of CH8. It becomes High if the voltage more than 2.1V is applied and becomes Low if the
voltage less than 0.4V is applied. In addition, UPIC8 terminal contains a built-in pull-down resistor of about 50kΩ.
13. SOFT START
It is a circuit to apply the soft start to the output voltage of DC/DC converter and prevent the rush current at the start-up.
Soft start time varies with the channels.
a.
CH1
・・・・・
Reaches the target voltage in 3.0 msec.
b.
CH3,4
・・・・・
Reaches the target voltage in 2.2 msec.
c.
CH2,5,6 ・・・・・
Reaches the target voltage in 4.4 msec.
d.
CH7,8
・・・・・
Reaches the target voltage in 5.4 msec.
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13/20
2010.11 - Rev.A
Technical Note
BD9757MWV
●CH8 Modulated light function explanation
VBAT
HS78H
OCP
VCCOUT
HS8L
To SCP
VCCOUT
INV8
1.0V
+
+
+
+
-
ERRAMP 8V
HS78H
Load
SW
Vo8(Feed Back ch8)
Lx8
N-ch
DRIVER
PWM COMP8
INV8I
VREGA1
1Fh(Fixed)
UPIC8
I/O
(schmitt)
counter for
tone setting
reaches 31
(5bit)
COUNT[4:0]
S
E
L
PGND678
+
+
VREGA_D
LED
INV8I
ERRAMP 8I
5->6bit
decode
latch
DACIN[5:0]
DAC
EN
LED Current
setting resister R
UVLO
EN
LOGIC
RESET
GEN
EN
UVLO
STBY
SOFT
START
SS_CLK
OSC
Detect Counter Detect Counter
for H Section for L Section
(6bit)
(6bit)
P&R area
Fig.28 CH8 block diagram
○Description of CH8 operation
EN, the signal for getting CH8 operated, is turned to H (EN=H) by maintaining the H interval that is shown by TEN and
from UPIC8 terminal (refer to Fig.29 EN start-up-G) .
EN signal is turned to L and CH8 is turned OFF by maintaining the L interval that is shown by TOFF and from UPIC8
terminal (refer to Fig.29 EN start-up-K ~ L) .
Moreover, UPIC8 terminal will not become L ever since EN starting-up, and if the H interval shown by TON is passed, then
the DAC input data (DACIN [4:0]) for setting of INV8I output voltage is started up by the state of MAX voltage setting (1Fh)
(refer to Fig.29 FULLON Mode-H ~ I).
As for the method to set the values except MAX voltage as INV8I voltage, first fix the UPIC8 terminal on interval L shown
by TCLR and then reset the counter for tone setting, before inputting only the number of times equivalent to the tone
intended for setting the UPIC8 terminal’s rising edge. Right after that, if it is fixed on interval H shown by TON, then the
number of count is latched, transmitted to DAC, and the voltage of INV8I is switched to the set voltage. At the time of
setting again, please repeat this operation (procedure). For the frequency of pulse inputted to UPIC8 terminal, please
follow the rules of TH and TL. (refer to Fig.29 Normal mode-K ~ N, and refer to P.2 for the rules).
Once the counter for tone setting reaches 31, 1Fh remains unchanged no matter how many times it is counted. If the
counter for tone setting needs to be cleared, please input the interval L of TCLR.
If the pulses less than TCLR is continued to be inputted to UPIC8 terminal after EN becomes H (EN=H) at the time of
starting up, then the value of counter for tone setting is undetermined, and DAC for INV8I output voltage setting is turned
OFF, therefore, please determine the set value with the time shown by TSET .
Furthermore, for the possible setting range of INV8I output voltage value, please refer to P.16(Fig.30 LED current value
setting).
○Points for attention at the time of CH8 starting up
Soft start is started when light control setting signal is inputted from UPIC8 terminal. At this moment it is necessary to
make any one of STB1 ~ 7 to be H, if OSC does not start oscillating after VREGA is started and UVLO is released, then
CH8 does not start up.
At the time of starting up there is no voltage enough for turning ON the LED, so the feedback on the side of INV8I does
not return,and it is soft-started by the voltage feedback from Vo8 to INV8.
Before the soft start internal is ended, the feedback (return) based on any current setting which is according to light
control setting is started. After soft-starting, any current setting is performed by changing the light control setting signal.
CH8 is turned off by making UPIC8 terminal to be L for a certain period of time.
Moreover, the interval of about 5.4mS from the time of UPIC8 terminal’s rising is taken as the soft start interval, and the
soft start is applied according to the current value originally set by light control from UPIC8 terminal. The change of light
control setting excepting turning off during this interval is not reflected.
○Recommended method of setting at the time of INV8I output voltage setting
If INV8I output setting value is made larger than previous setting value during all intervals but soft start interval (at the
time of starting up), it is recommended that the value of voltage is increased step by step with the smallest possible width
of step after fully evaluating the restriction at the soft side that controls rush current and switching and the vision of
brightness etc. in terms of set application.
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14/20
2010.11 - Rev.A
Technical Note
BD9757MWV
●Explanation on operation of CH8 5bit Counter + Register
Fig.29 Timing chart
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15/20
2010.11 - Rev.A
Technical Note
BD9757MWV
UPIC8
rising edge count
DAC input
DACIN[4:0]
INV8I
output voltage [V]
1
01h
0.100
2
02h
0.110
3
03h
0.120
4
04h
0.130
5
05h
0.140
6
06h
0.150
7
07h
0.160
8
08h
0.170
9
09h
0.180
10
0Ah
0.190
11
0Bh
0.200
12
0Ch
0.210
13
0Dh
0.220
14
0Eh
0.230
15
0Fh
0.240
16
10h
0.250
17
11h
0.260
18
12h
0.270
19
13h
0.280
20
14h
0.290
21
15h
0.300
22
16h
0.310
23
17h
0.320
24
18h
0.330
25
19h
0.340
26
1Ah
0.350
27
1Bh
0.360
28
1Ch
0.370
29
1Dh
0.380
30
1Eh
0.390
31
1Fh
0.400
Fig.30 LED current setting
(Note 1) LED current = INV8I voltage / resistance R for LED current setting
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16/20
2010.11 - Rev.A
Technical Note
BD9757MWV
●Setting method of IC peripheral components
(1) Design of feedback resistor constant
VOUT1～5
ERROR AMP
R1
VOUT8
VREF6
VOUT7
ERROR AMP
R1
INV
R2
R1
INV
VOUT6
ERROR AMP8V
INV8
R2
R2
VREF
0.8V
ERROR AMP
R1
NON
R2
VREF
1.0V
VREF
1.0V
Reference voltage is
connected to GND inside IC
Output level
L takes priority
ERROR AMP7I
INV8I
CH1～5 output voltage
R1 R2 0.8 [ V ] ・・・(1)
VO
R2
CH6 output voltage
R2
VO
1.0 [ V ] ・・・(2)
R1
CH7,8 output voltage
R1 R2 1.0 [ V ] ・・・(3)
VO
R2
CH8 output voltage
INV 8I
IO
[ A ] ・・・(4)
R3
R3
VREF
UPIC8 Setting according to
number of counts
(Refer to Fig.29 of page 15)
Fig.31 Feedback resistor setting method
(a) CH1 ~ 5 setting
The reference voltage of CH1 ~ 5’s ERROR AMP is 0.8V. Please refer to Formula (1) in Fig.31 for determining the
output voltage.
This IC incorporates built-in phase compensation. Please refer to Applied Circuit Diagram for setting the values of R1
& R2 and ensure that the setting values of R1 & R2 are of the order of several hundred kΩ.
(b) CH6 setting
The reference voltage of CH6’s ERROR AMP is connected to GND inside the IC. Therefore, a high-accuracy
regulator can be configured if setting by the feedback resistance between the outputs of VREF and CH5 as shown in
Fig.31. Please refer to Formula (2) in Fig.31 for determining the output voltage. R1 is recommended as more than
20kΩ because the current capacity of VREF is about 100μA.
(c) CH7 setting
The reference voltage of CH7’s ERROR AMP is 1.0V. Please refer to Formula (3) in Fig.31 for determining the output
voltage.
(d) CH8 setting
In the CH8 there are two ERROR AMPs which have different standards, and when used with constant current
feedback applied unilaterally to backlight etc., the over voltage protection can be operated unilaterally.
Over voltage setting and output current setting are respectively shown in Formula (3) and (4) in Fig.31.
The outputs of these two ERROR AMPs are controlled with L being given priority.
Therefore, when used under the control of only either of the two ensure that the INV terminal is used as GND Short.
CH6, CH7, and CH8 are of voltage mode control. Ensure that CH6, 7 and 8 are used by means of discontinuous
inductor current so as to secure the oscillation margin.
(2) Points for attention in terms of PCB layout of base-plate
○For a switching regulator, in principle a large current transiently flows through the route of power supply - coil - output
capacitor. Ensure that the wiring impedance is lowered as much as possible by making the pattern as wide as
possible and the layout as short as possible.
○Interference of power supply noise with feedback terminals (INV1 ~ 8I,NON6) may cause the output voltage to
oscillate. Ensure that the power supply noise’s interference is avoided by making the wiring between feedback
resistor and feedback terminal as short as possible.
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17/20
2010.11 - Rev.A
Technical Note
BD9757MWV
●PIN equivalent circuit
NON6
(Error amplifier’s non-inversion input)
INV1～INV8,INV8I
(Error amplifier’s inversion input)
VREGA
VCCOUT
VCCOUT
VREGA
NON6
INV
VREGA (REGA output)
VREF6
(CH6 Standard voltage output)
VCCOUT
VREGA
VCCOUT
VCCOUT
VREGA
VREF6
STB13, STB2, STB4, STB5,
STB6, STB7 (Operating when
CH1~7 ON/OFF switch is High)
UPIC8
(CH8 start signal, LED
modulated light signal input)
Hx1,2,3,4,5(Pch FET source terminal)
Lx1,2,3,4,5(Nch,Pch FET drain terminal)
PGND13,24,5 (output stage earthing terminal)
VREGA
Hx
VCCOUT
UPIC8
STB
VCCOUT
Lx
PGND
HS78H (high side SW input terminal)
HS7L, 8L (high side SW output terminal)
OUT5(CH5 power-MOSFET connection)
PGND567 (output stage earthing)
HS78H
VCCOUT
Lx7, 8 (Nch FET drain terminal)
PGND678
VCCOUT
Lx7,8
OUT6
HS7L,8L
VCCOUT
VCCOUT
PGND678
PGND678
Fig.32 PIN equivalent circuit
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18/20
2010.11 - Rev.A
Technical Note
BD9757MWV
●Notes for use
1.) Absolute Maximum Ratings
Although the quality of this product has been tightly controlled, deterioration or even destruction may occur if the absolute
maximum ratings, such as for applied pressure and operational temperature range, are exceeded. Furthermore, we are
unable to assume short or open mode destruction conditions. If special modes which exceed the absolute maximum
ratings are expected, physical safely precautions such as fuses should be considered.
2.) GND Potential
The potential of the GND pin should be at the minimum potential during all operation status. In addition, please try to do
not become electric potential below GND for the terminal other than NON6 including the transient phenomenon in practice.
Please do not go down below 0.3V for the NON6 terminal with transient phenomenon and the like when you use.
3.) Heat Design
Heat design should consider tolerance dissipation (Pd) during actual use and margins which should be set with plenty of
room.
4.) Short-circuiting Between Terminals and Incorrect Mounting
When attaching to the printed substrate, pay special attention to the direction and proper placement of the IC. If the IC is
attached incorrectly, it may be destroyed. Destruction can also occur when there is a short, which can be caused by
foreign objects entering between ouputs or an output and the power GND.
5.) Operation in Strong Magnetic Fields
Exercise caution when operating in strong magnet fields, as errors can occur.
6.) About common impedance
Please do sufficient consideration for the wiring of power source and GND with the measures such as lowering common
impedance, making ripple as small as possible (making the wiring as thick and short as possible, dropping ripple from
L.C) and the like.
7.) STB terminal voltage
Please set STB terminal voltage below 0.3V when each channel is put in stand-by state, and set it above 1.5V when each
channel is put in working condition. Please use the condenser below 0.01μF when the condenser is connected to the
STB terminal. As it will become the cause of the malfunction.
8.) Heat Protection Circuit (TSD circuit)
This IC has a built-in Temperature Protection Circuit (TSD circuit). The temperature protection circuit (TSD circuit) is only
to cut off the IC from thermal runaway, and has not been designed to protect or guarantee the IC. Therefore, the user
should not plan to activate this circuit with continued operation in mind.
9.) Because there are times when rush current flows instantaneously in internal logical uncertain state at the time of power
source turning on with CMOS IC, please pay attention to the power source coupling capacity, the width of GND pattern
wiring and power source, and the reel.
10.) Because there are times when rush current flows instantaneously due to the order of power source throwing in, lag with
CMOS IC where it has plural power sources, please pay attention to the power source coupling capacity, the width of
GND pattern wiring and power source, and the reel.
11.) IC Terminal Input
This IC is a monolithic IC, and between each element there is a P+ isolation and P substrate for element separation.
There is a P-N junction formed between this P-layer and each element’s N-layer, which makes up various parasitic
elements. For example, when resistance and transistor are connected with a terminal as in Fig.33:
○When GND>(terminal A) at the resistance, or GND>(terminal B) at the transistor (NPN),
the P-N junction operates as a parasitic diode.
○Also, when GND>(terminal B) at the transistor, a parasitic NPN transistor operates by the N-layer of other elements
close to the aforementioned parasitic diode.
With the IC’s configuration, the production of parasitic elements by the relationships of the electrical potentials is
inevitable. The operation of the parasitic elements can also interfere with the circuit operation, leading to malfunction
and even destruction. Therefore, uses which cause the parasitic elements to operate, such as applying voltage to the
input terminal which is lower than the GND (P-substrate), should be avoided.
Transistor (NPN)
(Terminal B)
B
C
E
N
+
P
P
N
+
P
N
P Board
+
P
N
Parasitic Element
GND
GND
P
N
N
(Terminal A)
+
P
N
P Board
Parasitic Element
～
～
Resistance
(Terminal A)
Parasitic Element
GND
GND
Fig.33 Simple Structure of Bipolar IC (Sample)
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19/20
2010.11 - Rev.A
Technical Note
BD9757MWV
●Ordering part number
B
D
9
Part No.
7
5
7
Part No.
M
W
V
-
Package
MWV: UQFN044V6060
E
2
Packaging and forming specification
E2: Embossed tape and reel
UQFN044V6060
6.0 ± 0.1
6.0±0.1
1.0MAX
11
E2
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
)
12
3.7± 0.1
44
0.5 ± 0.1
2000pcs
(0.22)
3.7±0.1
1
+0.03
0.02 -0.02
S
C0.2
Embossed carrier tape
Quantity
Direction
of feed
1PIN MARK
0.08 S
Tape
34
22
33
1.0
23
+0.05
0.4 0.2 -0.04
1pin
Reel
(Unit : mm)
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20/20
Direction of feed
∗ Order quantity needs to be multiple of the minimum quantity.
2010.11 - Rev.A
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; if flow soldering method is preferred, please consult with the
ROHM representative in advance.
For details, please refer to ROHM Mounting specification
Notice - GE
© 2014 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 our Products might fall under controlled goods prescribed by the applicable foreign exchange and foreign trade act,
please consult with ROHM representative 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. ROHM shall not be in any way responsible or liable
for infringement of any intellectual property rights or other damages arising from use of such information or data.:
2.
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 information contained in this document.
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 - GE
© 2014 ROHM Co., Ltd. All rights reserved.
Rev.002
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.
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