bl0202b ds en

High Efficiency
For LED Backlight 2ch LED Driver IC
BL0200 Series
General Descriptions
Package
BL0200 series are 2ch output LED driver IC for LED
backlight, and it can do dimming to 0.02 % by external
PWM signal.
This IC realizes a high efficiency by the boost
convertor control that absorbs variability on VF.
The product easily achieves high cost-performance
LED drive system with few external components and
enhanced protection functions.
SOP18
Not to scale
Features and Benefit
Boost convertor
● Current-Mode type PWM Control
● PWM frequency is 100 kHz o r 200 kHz
● Maximum On Duty is 90 %
Lineup
LED current control
● Individual PWM Dimming Control
● Analog Dimming
● High contrast ratio is 1 / 5000
● Accuracy of Reg output voltage is ± 1.5 % or ± 2 %
Protection functions
● Enable Function of IC (BL0202B, BL0202C)
● Error Signal Output (BL0200C)
● Overcurrent Protection for Boost Circuit (OCP)
----------------------------------------------Pulse-by-pulse
● Overcurrent Protection for LED Output (LED_OCP)
----------------------------------------------Pulse-by-pulse
● Overvoltage Protection (OVP) ----------- Auto restart
● Output Open/Short Protection ------------ Auto restart
● Thermal Shutdown (TSD)----------------- Auto restart
Products
Frequency
BL0202C
200 kHz
BL0202B
100 kHz
BL0200C
200 kHz
VREG
Accuracy
Built-in Function
± 1.5 %
Enable Function of
IC
±2%
Error Signal Output
Applications
● LED backlights
● LED lighting etc.
Typical Application Circuit
BL0200C
BL0202B/C
VCC
VREF
DRV1
VCC
OC1
PWM1
PWM2
EN
REG
COMP1
COMP2
GND
DRV1
VREF
OC1
PWM1
PWM2
SW1
SW1
ER
IFB1
IFB1
DRV2
DRV2
OC2
OC2
REG
OVP
COMP1
SW2
COMP2
GND
IFB2
TC_BL0202_1_R1
BL0200-DS Rev.2.2
Apr. 04, 2014
SANKEN ELECTRIC CO.,LTD.
OVP
SW2
IFB2
TC_BL0200C_1_R1
1
BL0200 Series
CONTENTS
Lineup ----------------------------------------------------------------------------------------- 1
Applications ---------------------------------------------------------------------------------- 1
1. Absolute Maximum Ratings --------------------------------------------------------- 3
2. Electrical characteristics ------------------------------------------------------------- 4
3. Functional Block Diagram ----------------------------------------------------------- 6
4. Pin List Table --------------------------------------------------------------------------- 7
5. Typical Application Circuit --------------------------------------------------------- 8
6. Package Diagram ---------------------------------------------------------------------- 9
7. Marking Diagram --------------------------------------------------------------------- 9
8. Functional Description -------------------------------------------------------------- 10
8.1
Startup Operation（BL0200C） -------------------------------------------- 10
8.2
Startup Operation（BL0202B, BL0202C） ------------------------------ 11
8.3
Constant Current Control Operation ----------------------------------- 12
8.4
PWM Dimming Function -------------------------------------------------- 13
8.5
Gate Drive --------------------------------------------------------------------- 13
8.6
Error Signal Output Function (BL0200C) ----------------------------- 14
8.7
Protection Function --------------------------------------------------------- 14
9. Design Notes --------------------------------------------------------------------------- 18
9.1
Peripheral Components ---------------------------------------------------- 18
9.2
Inductor Design Parameters----------------------------------------------- 18
9.3
PCD Trace Layout and Component Placement ----------------------- 19
10. Reference Design of Power Supply ----------------------------------------------- 21
10.1 BL0200C ----------------------------------------------------------------------- 21
10.2 BL0202B ----------------------------------------------------------------------- 21
OPERATING PRECAUTIONS -------------------------------------------------------- 25
IMPORTANT NOTES ------------------------------------------------------------------- 26
BL0200-DS Rev.2.2
Apr. 04, 2014
SANKEN ELECTRIC CO.,LTD.
2
BL0200 Series
1. Absolute Maximum Ratings
 The polarity value for current specifies a sink as "+," and a source as "−," referencing the IC.
 Unless otherwise specified, TA is 25 °C
Parameter
Symbol
Test
Conditions
Pins
Rating
Unit
REG Pin Source Current
IREG
1–9
−1
mA
OVP Pin Voltage
VOVP
2–9
− 0.3 to 5
V
PWM1 Pin Voltage
VPWM1
3–9
− 0.3 to 5
V
5–9
− 10
mA
Single pulse
5 µs
Notes
IFB1 Pin Clamp Current
IFB1
OC1 Pin Voltage
VOC1
6–9
− 0.3 to 5
V
DRV1 Pin Voltage
VDRV1
7–9
− 0.3 to VCC + 0.3
V
SW1 Pin Voltage
VSW1
8–9
− 0.3 to VCC + 0.3
V
VCC Pin Voltage
VCC
10 – 9
− 0.3 to 20
V
SW2 Pin Voltage
VSW2
11 – 9
− 0.3 to VCC + 0.3
V
DRV2 Pin Voltage
VDRV2
12 – 9
− 0.3 to VCC + 0.3
V
OC2 Pin Voltage
VOC2
13 – 9
− 0.3 to 5
V
IFB2 Pin Clamp Current
IFB2
14 – 9
− 10
mA
VPWM2
16 – 9
− 0.3 to 5
V
EN Pin Voltage
VEN
17 – 9
− 0.3 to 5
V
BL0202B
BL0202C
ER Pin Voltage
VER
17 – 9
− 0.3 to VREG
V
BL0200C
VREF Pin Voltage
VREF
18 – 9
− 0.3 to 5
V
Operating Ambient Temperature
Top
−
− 40 to 85
°C
Storage Temperature
Tstg
−
− 40 to 125
°C
Junction Temperature
Tj
−
150
°C
PWM2 Pin Voltage
BL0200-DS Rev.2.2
Apr. 04, 2014
Single pulse
5 µs
SANKEN ELECTRIC CO.,LTD.
3
BL0200 Series
2. Electrical characteristics
 The polarity value for current specifies a sink as "+," and a source as "−," referencing the IC.
 Unless otherwise specified, TA is 25 °C, VCC = 12 V
Parameter
Symbol
Test
Conditions
Pins
Min.
Typ.
Max.
Unit
10 – 9
8.5
9.6
10.5
V
7.8
8.6
9.2
8.0
9.1
10.0
10 – 9
−
5.3
8.0
mA
10 – 9
−
70
200
µA
Notes
Start / Stop Operation
Operation Start Voltage*
Operation Stop Voltage
Circuit Current in Operation
Circuit Current in
Non-Operation
REG Pin Output Voltage
VCC(ON)
10 – 9
VCC(OFF)
ICC(ON)
ICC(OFF)
VCC = 7.5 V
1–9
VREG
4.925 5.000 5.075
4.9
5.0
5.1
95
100
105
V
BL0202B
BL0202C
BL0200C
V
BL0202B
BL0202C
BL0200C
Oscillation
PWM Operation Frequency
Maximum ON Duty
Minimum ON Time
COMP Pin Voltage at
Oscillation Start
COMP Pin Voltage at
Oscillation Stop
fPWM1
fPWM2
7–9
12 – 9
DMAX1
DMAX2
tMIN1
tMIN2
7–9
12 – 9
7–9
12 – 9
4–9
15 – 9
4–9
15 – 9
VCOMP1(ON)
VCOMP2(ON)
VCOMP1(OFF)
VCOMP2(OFF)
VREF / IFB Pin
VREF Pin Minimum Setting
VREF(MIN)
Voltage
VREF Pin Maximum Setting
VREF(MAX)
Voltage
IFB Pin Voltage at COMP
VIFB1(COMP1)
Charge Switching
VIFB2(COMP2)
IFB Pin Overcurrent Protection
VIFB1(OCH)
High Threshold Voltage
VIFB2(OCH)
IFB Pin Overcurrent Protection
VIFB1(OCL)
Low Threshold Voltage
VIFB2(OCL)
IFB Pin Overcurrent Protection VIFB1(OCL-OFF)
Release Threshold Voltage
VIFB2(OCL-OFF)
IFB Pin Voltage at Auto Restart
VIFB1(AR)
Operation
VIFB2(AR)
IIFB1(B)
IFB Pin Bias Current
IIFB2(B)
Current Detection Threshold
Voltage
COMP Pin
COMP Pin Maximum Output
Voltage
VIFB1
VIFB2
BL0202B
kHz
190
200
210
85
90
95
%
200
310
400
ns
0.35
0.50
0.65
V
0.10
0.25
0.40
V
VREF = 0 V
18 – 9
0.05
0.25
0.45
V
VREF = 5 V
18 – 9
1.75
2.00
2.35
V
0.55
0.60
0.65
V
3.8
4.0
4.2
V
1.9
2.0
2.1
V
1.5
1.6
1.7
V
0.45
0.50
0.55
V
−
−
1
µA
0.98
1.00
1.02
VREF = 1 V
VREF = 1 V
VREF = 1 V
VREF = 1 V
VIFB1 = 5 V
VIFB2 = 5 V
VREF = 1 V
VCOMP1(MAX) VIFB1 = 0.7 V
VCOMP2(MAX) VIFB2 = 0.7 V
5–9
14 – 9
5–9
14 – 9
5–9
14 – 9
5–9
14 – 9
5–9
14 – 9
5–9
14 – 9
5–9
14 – 9
4–9
15 – 9
V
0.985 1.000 1.015
4.8
5.0
−
BL0200C
BL0202C
BL0202B
BL0202C
BL0200C
V
* VCC(ON) > VCC(OFF)
BL0200-DS Rev.2.2
Apr. 04, 2014
SANKEN ELECTRIC CO.,LTD.
4
BL0200 Series
Parameter
COMP Pin Minimum Output
Voltage
Transconductance
COMP Pin Source Current
COMP Pin Sink Current
COMP Pin Charge Current at
Startup
COMP Pin Reset Current
Symbol
VCOMP1(MIN)
VCOMP2(MIN)
gm
ICOMP1(SRC)
ICOMP2(SRC)
ICOMP1(SNK)
ICOMP2(SNK)
ICOMP1(S)
ICOMP2(S)
ICOMP1(R)
ICOMP2(R)
Test
Conditions
Pins
4–9
15 – 9
−
VIFB1 = 0.7 V 4 – 9
VIFB2 = 0.7 V 15 – 9
VIFB1 = 1.5 V 4 – 9
VIFB2 = 1.5 V 15 – 9
VCOMP1 = 0 V 4 – 9
VCOMP2 = 0 V 15 – 9
4–9
15 – 9
VIFB1 = 2.0 V
VIFB2 = 2.0 V
Min.
Typ.
Max.
Unit
−
0
0.2
V
−
640
−
µS
−77
−57
−37
µA
37
57
77
µA
−19
−11
−3
µA
200
360
520
µA
Notes
EN Pin
Operation Start EN Pin Voltage
VEN(ON)
17 – 9
1.2
2.0
2.6
V
Operation Stop EN Pin Voltage
VEN(OFF)
17 – 9
0.8
1.4
1.8
V
EN Pin Sink Current
IEN
VEN = 3 V
17 – 9
20
55
120
µA
ER Pin
ER Pin Sink Current during
Non-Alarm
IER
VER = 1 V
17 – 9
2.5
4.4
6.3
mA
VCOMP1
= VCOMP2
= 4.5 V
6–9
13 – 9
0.57
0.60
0.63
V
BL0202B
BL0202C
BL0200C
Boost Parts Overcurrent Protection (OCP)
OC Pin Overcurrent Protection
Threshold Voltage
VOCP1
VOCP2
Overvoltage Protection (OVP)
OVP Pin Overvoltage
Protection Threshold Voltage
OVP Pin OVP Release
Threshold Voltage
VOVP
2–9
2.85
3.00
3.15
V
VOVP(OFF)
2–9
2.60
2.75
2.90
V
VPWM1(ON)
VPWM2(ON)
VPWM1(OFF)
VPWM2(OFF)
RPWM1
RPWM2
3–9
16 – 9
3–9
16 – 9
3–9
16 – 9
1.4
1.5
1.6
V
0.9
1.0
1.1
V
100
200
300
kΩ
ISW1(SRC)
ISW2(SRC)
ISW1(SNK)
ISW2(SNK)
IDRV1(SRC)
IDRV2(SRC)
IDRV1(SNK)
IDRV2(SNK)
8–9
11 – 9
8–9
11 – 9
7–9
12 – 9
7–9
12 – 9
−
−85
−
mA
−
220
−
mA
−
−0.36
−
A
−
0.85
−
A
−
125
−
−
°C
−
−
65
−
°C
−
−
−
95
°C/W
PWM Pin
PWM Pin ON Threshold
Voltage
PWM Pin OFF Threshold
Voltage
PWM Pin Impedance
SW / DRV Pin
SW Pin Source Current
SW Pin Sink Current
DRV Pin Source Current
DRV Pin Sink Current
Thermal Shutdown Protection (TSD)
Thermal Shutdown Activating
Tj(TSD)
Temperature
Hysteresis Temperature of TSD
Tj(TSD)HYS
Thermal Resistance
Thermal Resistance from
Junction to Ambient
BL0200-DS Rev.2.2
Apr. 04, 2014
θj-A
SANKEN ELECTRIC CO.,LTD.
5
BL0200 Series
3. Functional Block Diagram
BL0202B, BL0202C
VCC
10
EN
17
PWM1
VCC UVLO
REG ON/OFF
3
PWM1 Pulse
Detector
16
PWM2 Pulse
Detector
1
REG
8
SW1
11
SW2
7
DRV1
12
DRV2
6
OC1
13
OC2
VCC
Drive
TSD
VCC
PWM2
Drive
PWM OSC
Main Logic
OVP
2
VREF
18
IFB1
IFB2
VCC
Overvoltage
Detector
Drive
VCC
Abnormal
Detector
5
Feedback1
Control
14
Feedback2
Control
Auto Restart
Protection
Drive
OC1 Control
Slope
Compensation
OC2 Control
15
4
COMP2
9
COMP1
GND
BD_BL202_R1
BL0200C
VCC
10
1
REG
8
SW1
11
SW2
7
DRV1
12
DRV2
17
ER
6
OC1
13
OC2
VCC
VCC UVLO
REG ON/OFF
PWM1
3
PWM2
16
PWM1 Pulse
Detector
Drive
TSD
VCC
Drive
PWM2 Pulse
Detector
PWM OSC
Main Logic
OVP
2
VREF
18
Overvoltage
Detector
VCC
Drive
VCC
IFB1
IFB2
Abnormal
Detector
5
Feedback1
Control
14
Feedback2
Control
Drive
Auto Restart
Protection
OC1 Control
Slope
Compensation
OC2 Control
15
4
COMP2
BL0200-DS Rev.2.2
Apr. 04, 2014
COMP1
9
GND
SANKEN ELECTRIC CO.,LTD.
BD_BL200_R1
6
BL0200 Series
4. Pin List Table
Number
Name
Function
REG
1
18
VREF
1
REG
Internal regulator output
OVP
2
17
EN / ER
2
OVP
Overvoltage detection signal input
PWM1
3
16
PWM2
3
PWM1
PWM dimming signal input (1)
COMP1
4
15
COMP2
4
COMP1
IFB1
5
14
IFB2
5
IFB1
OC1
6
13
OC2
6
OC1
DRV1
7
12
DRV2
7
DRV1
Phase compensation and soft-start setting (1)
Feedback signal input of current detection
(1)
Current mode control signal input (1) and
overcurrent protection signal input (1)
Boost MOSFET gate drive output (1)
SW1
8
11
SW2
8
SW1
Dimming MOSFET gate drive output (1)
GND
9
10
VCC
9
GND
Ground
10
VCC
Power supply voltage input
11
SW2
Dimming MOSFET gate drive output (2)
12
DRV2
13
OC2
14
IFB2
15
COMP2
Boost MOSFET gate drive output (2)
Current mode control signal input (2) and
overcurrent protection signal input (2)
Feedback signal input of current detection
(2)
Phase compensation and soft-start setting (2)
16
PWM2
EN
ER
VREF
PWM dimming signal input (2)
Enable signal input (BL0202B, BL0202C)
Error signal output (BL0200C)
Detection voltage setting
17
18
BL0200-DS Rev.2.2
Apr. 04, 2014
SANKEN ELECTRIC CO.,LTD.
7
BL0200 Series
5. Typical Application Circuit
LED_OUT2(+)
F1
D9
LED_OUT2(-)
P_IN
L2
D6
LED_OUT1(+)
R50
L1
D1
D8
Q4
C21
LED_OUT1(-)
C18
R22
D10
R45
Q3
R49
Q2
R63
C1
R47
D3
R17
R61
D7
R44
R1
C2
R2
Q1
R21
R48
R15
D2
R19
R16
R3
R24
R20
R4
P_GND
R46
C8
R62
R18
VCC
SW2
OC2
IFB2
COMP2
R38
PWM2_IN
PWM2
ON/OFF
EN
R39
VCC_IN
VREF
R41
C7
S_GND
C11
C19
C22
C13
8
12
7
13
14
6
5
15
4
16
3
17
2
18
1
C14
GND
SW1
DRV1
OC1
R23
IFB1
COMP1 R27
PWM1
OVP
REG
C12
C10
R34
C4
R42
R37
C20
R32
R36
11
BL0202
DRV2
9
U1
10
R35
C15
R33
C16
C3
C5
C6
R26
R25
PWM1_IN
TC_BL0202_2_R1
Figure 5-1 BL0202B and BL0202C Typical Application Circuit
LED_OUT2(+)
F1
D9
LED_OUT2(-)
P_IN
L2
D6
LED_OUT1(+)
R50
L1
D1
D8
Q4
C21
R22
D10
R45
Q3
R49
Q2
R63
C1
R47
R1
C2
D3
R17
R61
D7
R44
LED_OUT1(-)
C18
R2
Q1
R21
R48
R15
D2
R19
R16
R3
R24
R20
R4
P_GND
R46
C8
R62
R18
VCC
SW2
OC2
IFB2
PWM2_IN
COMP2
R38
PWM2
R39
ER_OUT
ER
VREF
Q5
VCC_IN
9
11
8
12
7
13
14
6
5
15
4
16
3
17
2
18
1
GND
SW1
DRV1
OC1
COMP1 R27
PWM1
OVP
REG
R31
Q6
R30
R36
C11 C19
C22
C13
C4
R42
R41
C7
C20
R32
C9
C12
R40
R29
ON/OFF
R23
IFB1
R37
R28
S_GND
U1
BL0200C
DRV2
10
C14
C10
R34
R35
R33
C15
C16
C3
C5
C6
R26
R25
PWM1_IN
TC_BL0202_2_R1
Figure 5-2 BL0200C Typical Application Circuit
BL0200-DS Rev.2.2
Apr. 04, 2014
SANKEN ELECTRIC CO.,LTD.
8
BL0200 Series
6. Package Diagram
 SOP18
NOTES：
1) Dimension is in millimeters
2) Pb-free. Device composition compliant with the RoHS directive
7. Marking Diagram
18
B L 0 2 0 × ×
Part Number
S K Y M D
1
Lot Number
Y is the last digit of the year (0 to 9)
M is the month (1 to 9, O, N or D)
D is a period of days (1 to 3) :
1 : 1st to 10th
2 : 11th to 20th
3 : 21st to 31st
Sanken Control Number
BL0200-DS Rev.2.2
Apr. 04, 2014
SANKEN ELECTRIC CO.,LTD.
9
BL0200 Series
VCC（OFF）
one package, and can independently control each
output current.
 The operation of control circuit for LED_OUT1 is
same operation as the control circuit for
LED_OUT2.
8.1 Startup Operation（BL0200C）
Figure 8-1 shows the VCC pin peripheral circuit. The
VCC pin is the power supply input for control circuit
from the external power supply.
When the VCC pin voltage increases to the Operation
Start Voltage, VCC(ON) = 9.6 V, the control circuit starts
operation. After that, when the PWM pin voltage exceeds
the PWM Pin ON Threshold Voltage, VPWM(ON) of 1.5 V
(less than absolute maximum voltage of 5 V), the COMP
Pin Charge Current at Startup, ICOMP(S) = −11 µA, flows
from the COMP pin. This charge current flows to
capacitors at the COMP pin. When the COMP pin
voltage increases to the COMP Pin Voltage at Oscillation
Start, VCOMP(ON) = 0.50 V or more, the control circuit
starts switching operation.
As shown in Figure 8-2, when the VCC pin voltage
decreases to the Operation Stop Voltage, VCC(OFF) = 9.1 V,
the control circuit stops operation, by the UVLO
(Undervoltage Lockout) circuit, and reverts to the state
before startup.
Start
 All of the parameter values used in these descriptions
are typical values, unless they are specified as
minimum or maximum.
 With regard to current direction, "+" indicates sink
current (toward the IC) and "–" indicates source
current (from the IC).
 The IC incorporates two boost converter circuits in
ICC
ICC（ON）
Stop
8. Functional Description
VCC（ON）
VCC
Figure 8-2 VCC versus ICC
When the on-duty of the PWM dimming signal is
small, the charge current at the COMP pin is controlled
as follows in order to raise the output current quickly at
startup.
Figure 8-3 shows the operation waveform with the
PWM dimming signal at startup.
VCC pin voltage
VCC(ON)
0
Constant current control
IFB pin voltage
VREF pin voltage
VIFB(COMP.VR)
0
PWM pin
Dimming signal
0
COMP pin
charge current
0
ICOMP(S)
ICOMP(SRC)
COMP pin
voltage
External power supply
10
PWM1
VCC
U1
COMP1
VCOMP(ON)
0
IC switching
status OFF
ON
GND
4
C7
3
Figure 8-3 Startup operation during PWM dimming
9
C8
C16
R42
C15
Figure 8-1 VCC pin peripheral circuit
BL0200-DS Rev.2.2
Apr. 04, 2014
While the IFB pin voltage increases to the IFB Pin
Voltage at COMP Charge Switching, VIFB(COMP.VR), a
capacitors at the COMP pin are charged by ICOMP(S) = −11
µA. During this period, they are charged by the COMP
Pin Source Current, ICOMP(SRC) = −57 µA, when the PWM
pin voltage is 1.5 V or more. Thus, the COMP pin
voltage increases immediately. When the IFB pin voltage
increases to VIFB(CMP1.VR) or more, the COMP pin source
current is controlled according to the feedback amount,
and the output current is controlled to be constant. The
on-duty gradually becomes wide according to the
SANKEN ELECTRIC CO.,LTD.
10
BL0200 Series
increase of the COMP pin voltage, and the output power
increases (Soft start operation). Thus, power stresses on
components are reduced.
When the VCC pin voltage decreases to the operation
stop voltage or less, or the Auto Restart operation (see
the Section 8.7 Protection Function) after protection is
achieved, then the control circuit stops switching
operation, and capacitors at the COMP pin are
discharged by the COMP Pin Reset Current,
ICOMP(R) = 360 µA simultaneously. The soft start
operation is achieved at restart.
The IC is operated by Auto Restart 1 at startup
operation. See the Section 8.7 Protection Function about
the caution of startup operation.
VIFB(COMP.VR) is determined by the VREF pin voltage,
as shown in Figure 8-4. When VREF pin voltage is 1V,
the value of VIFB(COMP.VR) becomes 0.60 V.
VIFB(COMP.VR)
1.2V
VCC pin voltage decreases to the Operation Stop
Voltage, VCC(OFF) = 8.6 V, the control circuit stops
operation, by the UVLO (Undervoltage Lockout) circuit,
and reverts to the state before startup.
The value of R39 connected to EN pin is set as
follows;
R 39 

VEN _ IN  VEN( ON ) (max)
I EN (max)
VEN _ IN  2.6(V)
120(A)
(8-1)
Where,
VEN_IN is EN pin input voltage (less than absolute value
of EN pin voltage, 5 V ). VEN(ON)(max) is the maximum
rating of EN Pin Operation Start Voltage. IEN(max) is
the maximum rating of EN Pin Sink Current.
In case VEN_IN = 3.5V, the value of R39 should be set
7.5 kΩ or less.
0.6V
External power supply
0.15V
8
1V
2V
VREF pin voltage
Figure 8-4 VREF pin voltage versus IFB pin voltage at
COMP charge switching
8.2 Startup Operation（BL0202B, BL0202C）
BL0202B and BL0202C have Enable Function. Figure
8-5 shows the peripheral circuit of VCC pin and EN pin,
Figure 8-6 shows the operational waveforms.
The VCC pin is the power supply input for control
circuit from the external power supply. The EN pin is
ON/OFF signal input from the external circuit.
When the both VCC pin voltage, VCC, and EN pin
voltage, VEN, increase to the each operation voltage or
more, the control circuit starts operation (VCC ≥
VCC(ON) = 9.6 V and VEN ≥ VEN(ON) = 2.0 V).
After that, when the PWM pin voltage exceeds the
PWM Pin ON Threshold Voltage, VPWM(ON) of 1.5 V
(less than absolute maximum voltage of 5 V), the COMP
Pin Charge Current at Startup, ICOMP(S) = −11 µA, flows
from the COMP pin. This charge current flows to
capacitors at the COMP pin. When the COMP pin
voltage increases to the COMP Pin Voltage at Oscillation
Start, VCOMP(ON) = 0.50 V or more, the control circuit
starts switching operation.
As shown in Figure 8-2, when the EN pin voltage
decreases to the Operation Stop Voltage VEN(OFF) = 1.4 V
or less, the control circuit stops operation. And when the
BL0200-DS Rev.2.2
Apr. 04, 2014
5
R39
EN
COMP1
C8
C7
3
PWM1
ON/OFF
0.25V
BL0202B/C
VCC
GND
4
VEN_IN
C22
9
R42
C16
C15
Figure 8-5 The peripheral circuit of VCC pin and EN pin
VCC pin voltage
VCC(ON)
VCC(OFF)
0
EN pin voltage
VEN(ON)
VEN(OFF)
0
REG pin voltage
0
COMP pin voltage
VCOMP(ON)
VCOMP(OFF)
0
IC switching status
OFF
ON
OFF
ON
OFF
Figure 8-6 Operational waveforms
SANKEN ELECTRIC CO.,LTD.
11
BL0200 Series
When the on-duty of the PWM dimming signal is
small, the charge current at the COMP pin is
controlled as follows in order to raise the output
current quickly at startup.
Figure 8-7 shows the operation waveform with the
PWM dimming signal at startup.
VCC pin voltage
capacitors at the COMP pin are discharged by the COMP
Pin Reset Current, ICOMP(R) = 360 µA. Because the
on-duty gradually becomes wide after cycling power to
the IC, the soft start operation is achieved at restart.
The IC is operated by Auto Restart 1 at startup
operation. See the Section 8.7 Protection Function about
the caution of startup operation.
VIFB(COMP.VR) is determined by the VREF pin voltage as
shown in Figure 8-4.
VCC(ON)
0
8.3 Constant Current Control Operation
EN pin voltage
VEN(ON)
0
Constant current control
IFB pin voltage
VREF pin voltage
VIFB1(COMP.VR)
0
PWM pin
Dimming signal
0
COMP pin
charge current
0
ICOMP(S)
Figure 8-8 shows the IFB pin peripheral circuit.
When the dimming MOSFET (Q2, Q4) turns on, the
LED output current, IOUT(CC), is detected by the current
detection resistor, R15 and R61. The IC compares the
IFB pin voltage with the VREF pin voltage by the
internal error amplifier, and controls the IFB pin voltage
so that it gets close to the VREF pin voltage.
The reference voltage at the VREF pin is the divided
voltage of the REG pin voltage, VREG = 5 V, by R32 to
R35, and thus this voltage can be externally adjusted.
The setting current, IOUT(CC), of the LED_OUT can be
calculated as follows.
ICOMP(SRC)
I OUT ( CC) 
COMP pin
voltage
ON
Figure 8-7 Startup operation during PWM dimming
U1
10
VCC
While the IFB pin voltage increases to the IFB Pin
Voltage at COMP Charge Switching, VIFB(COMP.VR), a
capacitors at the COMP pin are charged by ICOMP(S) = −11
µA. During this period, they are charged by the COMP
Pin Source Current, ICOMP(SRC) = −57 µA, when the PWM
pin voltage is 1.5 V or more. Thus, the COMP pin
voltage increases immediately.
When the IFB pin voltage increases to VIFB(COMP.VR) or
more, the COMP pin source current is controlled
according to the feedback amount, and the output current
is controlled constant.
The on-duty gradually becomes wide according to the
increase of the COMP pin voltage, and the output power
increases (Soft start operation). Thus, power stresses on
components are reduced.
When the VCC pin voltage or EN pin voltage
decreases to the operation stop voltage or less, or the
Auto Restart operation (see the Section 8.7 Protection
Function) after protection is achieved, then the control
circuit stops switching operation, and simultaneously
BL0200-DS Rev.2.2
Apr. 04, 2014
(8-2)
Where:
VREF is the VREF pin voltage. The value is
recommended to be 0.5 V to 2.0 V.
RESN is the value of output current detection resistor
VCOMP(ON)
0
IC switching
status OFF
VREF
R SEN
REG
5V
1
LED_OUT1(+)
R34
IOUT(CC)
R35
Error Amp.
VREF 18
R32
R33
Abnormal
Detector
LED_OUT1(-)
Q2
IFB1 5
Output current
detection resistor
R15
Figure 8-8 IFB pin peripheral circuit
SANKEN ELECTRIC CO.,LTD.
12
BL0200 Series
8.4 PWM Dimming Function
8.5 Gate Drive
Figure 8-9 shows the peripheral circuit of PWM pin
and SW pin.
The PWM pin is used for the PWM dimming signal
input. The SW pin drives the gate of external dimming
MOSFET (Q2, Q4). The SW pin voltage is turned on /
off by PWM signal and thus the dimming of LED is
controlled by PWM signal input.
As shown in Figure 8-10, when the PWM pin voltage
becomes the PWM Pin ON Threshold Voltage,
VPWM(ON) = 1.5 V or more, the SW pin voltage becomes
VCC. When the PWM pin voltage becomes the PWM Pin
OFF Threshold Voltage, VPWM(OFF) = 1.0 V or less, the
SW pin voltage becomes 0.1 V or less. The PWM pin has
the absolute maximum voltage of −0.3 V to 5 V, and the
input impedance, RPWM, of 200 kΩ.
The PWM dimming signal should meet these
specifications and threshold voltages of VPWM(ON) and
VPWM(OFF).
3
PWM_IN
U1
PWM1
LED
PWM Pulse
Detector
Drive
● Power MOSFET should be selected so that these
VGS(th) threshold voltages are less than VCC enough
over entire operating temperature range.
● Peripheral components of Power MOSFET, gate
resistors and diode, affect losses of power MOSFET,
gate waveform (ringing caused by the printed circuit
board trace layout), EMI noise, and so forth, these
values should be adjusted based on actual operation in
the application.
● The resistors between gate and source (R19, R24, R47
and R63) are used to prevent malfunctions due to steep
dv/dt at turn-off of the power MOSFET, and these
resistors are connected near each the gate of the power
MOSFETs and the ground line side of the current
detection resistance. The reference value of them is
from 10 kΩ to 100 kΩ.
LED_OUT1(−)
VCC
PWM OSC
Main Logic
LED_OUT1(+)
Figure 8-11 shows the peripheral circuit of DRV pin
and SW pin and FSET pin. The DRV pin is for boost
MOSFET, Q1 and Q3. The SW pin is for dimming
MOSFET, Q2 and Q4. Table 8-1 shows drive voltages
and currents of DRV pin and SW pin.
SW1 8
Q2
Table 8-1 Drive voltage and current
R15
Pins
Figure 8-9 The peripheral circuit of PWM pin
and SW pin.
Drive voltage, VDRV
Drive current, IDRV
High
Low
Source
Sink
DRV
VCC
≤ 0.1 V
−0.36 A
0.85 A
SW
VCC
≤ 0.1 V
−85 mA
220 mA
PWM pin voltage
VPWM(ON)
D1
LED_OUT1(+)
L1
VPWM(OFF)
C1
Q1
R17
０
R22
Time
SW pin voltaege
R16
VCC
7
≤ 0.1V
C2
U1
VCC
Q2
D2
R19
R20
R21
D3
R24
R15
DRV1
Drive
０
Time
PWM OSC
Main Logoc
VCC
Drive
SW1 8
GND 9
Figure 8-10 The waveform of PWM pin and SW pin
Figure 8-11 The peripheral circuit of DRV pin,
SW pin and FSET pin
BL0200-DS Rev.2.2
Apr. 04, 2014
SANKEN ELECTRIC CO.,LTD.
13
BL0200 Series
8.6 Error Signal Output Function (BL0200C)
When an external circuit such as microcomputer uses
the error signal output, configure the peripheral circuit of
ER pin using the pull-up resistor, R40 and the protection
resistor of ER pin, R39, as shown in Figure 8-12.
The ER pin is connected to internal switch. When the
protection function is active, the internal switch becomes
OFF and ER_OUT becomes REG pin voltage from 0 V.
The resistances of R39 and R40 are about 10 kΩ.
REG
1
R40
ER
ER_OUT
17
Auto restart
protection
GND
7
R39
C12
Figure 8-12 ER pin peripheral circuit
As shown in Table 8-2, the IC performs protection
operations according to kind of abnormal state. In all
protection functions, when the fault condition is removed,
the IC returns to normal operation automatically. The
intermitted oscillation operation reduces stress on the
power MOSFET, the secondary rectifier diode, and so
forth.
Table 8-2 Relationship between a kind of abnormal state
and protection operations
Protection
Operations
Abnormal States
2
3
4
5
6
7
8
Overcurrent of boost circuit (OCP)
Overcurrent of LED output
(LED_OCP)
Overvoltage of LED_OUT(+)
(OVP)
Short mode between
LED_OUT(−) and GND
Short mode of LED current
detection resistor (RSEN_Short)
Short mode of both ends of LED
output
Open mode of LED current
detection resistor (RSEN_Open)
Overtemperature of junction of IC
(TSD)
BL0200-DS Rev.2.2
Apr. 04, 2014
Table 8-3 shows the Auto Restart 1 oscillation time,
tARS1, tARS2, and the Auto Restart 1 non-oscillation time,
tAROFF1, at on-duty = 100 %.
Table 8-3 Oscillation time and non-oscillation time
(at on-duty = 100 %)
8.7 Protection Function
1
Auto Restart 1:
As shown in Figure 8-13, the IC repeats an intermitted
oscillation operation, after the detection of any one of
abnormal states 1 to 5 in Table 8-2. This intermitted
oscillation is determined by tARS1 or tARS2, and tAROFF1.
The tARS1 is an oscillation time in the first intermitted
oscillation cycle, TAR1. The tARS2 is an oscillation time in
the second and subsequent intermitted oscillation cycle,
TAR2. The tAROFF1 is a non-oscillation time in all
intermitted oscillation cycle.
In case PWM dimming frequency is low and the
on-duty is small, the startup operation, the restart
operation from on-duty = 0 % and the restart operation
from intermitted oscillation operation need a long time.
Thus the value of tARS1 and tARS2 depend on frequency
and on-duty of the PWM dimming signal, as shown in
Figure 8-15 and Figure 8-16 for BL020×C, Figure 8-17
and Figure 8-18 for BL0202B.
Auto
Restart 1
BL0200C
BL0202C
BL0202B
Oscillation
time, tARS1
Oscillation
time, tARS2
non-oscillation
time, tAROFF1
31 ms
20.5 ms
About 635 ms
61.4 ms
41.0 ms
About 1.3 s
Auto Restart 2:
As shown in Figure 8-14, the IC stops the switching
operation immediately after the detection of abnormal
states 6 or 7 in Table 8-2, and repeats an intermitted
oscillation operation. In the intermitted oscillation cycle,
the tARSW is an oscillation time, the tAROFF1 is a
non-oscillation time.
The value of tARSW is a few microseconds. The value
of tARS2 is derived from Figure 8-18, and tAROFF2 is
calculated as follows:
t AROFF 2  t ARS 2  t ARSW  t AROFF 1
(8-3)
In case the on-duty is 100%, the value of tAROFF2
becomes as follows:
Auto
Restart 2
Auto
Restart 3
L0200C、BL0202C：
tAROFF2 ≒ 20.5 + 635 = 655.5 (ms)
BL0202B：
tAROFF2 ≒ 0.041 + 1.3 = 1.341 (s)
SANKEN ELECTRIC CO.,LTD.
14
BL0200 Series
Auto Restart 3:
The IC stops the switching operation immediately after
the detection of abnormal states 8 in Table 8-2, and keeps
a non-oscillation.
SW pin
voltage
tARS1
tARS2
1500
1000
500
Return to
normal
operation
tARS2
fDM = 100 Hz
fDM = 300 Hz
2000
tARS1 (ms)
Release
Abnormal
state
fDM : PWM dimming frequency
2500
0
0.01
0.1
1
10
100
Duty (%)
０
tAROFF1
TAR1
tAROFF1
tAROFF1
TAR2
TAR2
Time
Figure 8-15 PWM dimming on-duty vs. tARS1 (BL020×C)
fDM : PWM dimming frequency
1400
fDM = 100 Hz
fDM = 300 Hz
1200
Figure 8-13 Auto Restart 1
tARS1 (ms)
1000
Release
Abnormal
state
tARSW
SW pin
voltage
tAROFF2
Return to
normal
operation
tARSW
600
400
200
0
0.01
tAROFF2
tAROFF2
tARS2
tARS2
０
tAROFF1
800
tAROFF1
Time
0.1
1
Duty (%)
10
100
Figure 8-16 PWM dimming on-duty vs. tARS2 (BL020×C)
tAROFF1
fDM : PWM dimming frequency
2500
Figure 8-14 Auto Restart 2
fDM = 100 Hz
fDM = 300 Hz
tARS1 (ms)
2000
1500
1000
500
0
0.01
0.1
1
Duty (%)
10
100
Figure 8-17 PWM dimming on-duty vs. tARS1 (BL0202B)
fDM : PWM dimming frequency
1400
fDM = 100 Hz
fDM = 300 Hz
1200
tARS2 (ms)
1000
800
600
400
200
0
0.01
0.1
1
10
100
Duty (%)
Figure 8-18 PWM dimming on-duty vs. tARS2 (BL0202B)
BL0200-DS Rev.2.2
Apr. 04, 2014
SANKEN ELECTRIC CO.,LTD.
15
BL0200 Series
The operating condition of Auto Restart 1 and 2 is as
follows:
< The operating condition of Auto Restart 1 >
The Auto Restart 1 is operated by the detection signals
of the OC pin or IFB pin.
● Operation by the detection signal of OC pin:
When the OC pin voltage increase to the OC Pin
Overcurrent
Protection
Threshold
Voltage,
VOCP = 0.60 V, or more, the operation of the IC
switches to Auto Restart 1. When the fault condition is
removed and the OC pin voltage decreases to under
VOCP, the IC returns to normal operation automatically.
● Operation by the detection signal of IFB pin:
As shown in Figure 8-19, IFB pin has two types of
threshold voltage. These threshold voltages depend on
the VREF pin voltage, as shown in Figure 8-20.
IFB pin
voltage
VIFB(OCL.VR)
VIFB(OCL-OFF.VR)
VIFB(AR.VR)
VIFB(COMP)
０
Return to normal operation
SW pin
voltage
Time
０
Time
1) In case IFB pin voltage increased
When the FB pin voltage increase to VIFB(OCL.VR) in
Figure 8-20, or more, the operation of the IC switches
to Auto Restart 1. When the fault condition is
removed and the IFB pin voltage decreases to
VIFB(OCL-OFF.VR) in Figure 8-20, or less, the IC returns
to normal operation automatically.
2) In case IFB pin voltage decreased
When the FB pin voltage decrease to VIFB(AR.VR) in
Figure 8-20, or more, the operation of the IC switches
to Auto Restart 1. When the fault condition is
removed and the IFB pin voltage increases to above
VIFB(COMP), the IC returns to normal operation
automatically.
< The operating condition of Auto Restart 2 >
The Auto Restart 2 is operated by the detection signal
of the IFB pin.
As shown in Figure 8-21, when the FB pin voltage
increase to the IFB Pin Overcurrent Protection High
Threshold Voltage, VIFB(OCH) = 4.0 V, or more, the
operation of the IC switches to Auto Restart 2, and the IC
stops switching operation immediately. When the fault
condition is removed and the IFB pin voltage decreases
to under VIFB(OCH), the operation of the IC switches to
Auto Restart 1.
IFB pin
voltage
VIFB(OCH)
VIFB(OCL-OFF.VR)
Auto Restart 1
０
Figure 8-19 IIFB pin threshold voltage
and Auto Restart 1 operation
IFB pin threshold voltages (V)
VIFB(OCL.VR) : IFB Pin Overcurrent Protection Low Threshold Voltage
VIFB(OCL-OFF.VR) :IFB Pin Overcurrent Protection Release Threshold Voltage
VIFB(AR.VR) :IFB Pin Auto Restart Operation Threshold Voltage
10.0
VIFB(OCL.VR)
4.0V
3.2V
VIFB(OCL.VR)
VIFB(AR.VR)
1.0V
1.0
0.5V
0.4V
0.125V
0.1
0.1
Return to normal
operation
SW pin
voltage
０
Time
Auto Restart 2
Auto Restart 1
Figure 8-21 IFB pin threshold voltage
and Auto Restart 2 operation
< Caution of startup operation >
When the LED current is low and the IFB pin voltage
is less than VIFB(AR.BR), during startup for example, the IC
is operated by Auto Restart 1. If the startup time is too
long, the IC operation becomes the intermitted oscillation
by the Auto Restart 1. It becomes cause of the fault
startup operation, thus the startup time should be set less
than tARS1 in Figure 8-13.
1.0
0.25V
VREF pin voltage (V)
Figure 8-20 VREF pin voltage versus
IFB pin threshold voltages
BL0200-DS Rev.2.2
Apr. 04, 2014
SANKEN ELECTRIC CO.,LTD.
16
BL0200 Series
The protection operation according to the abnormal
states in Table 8-2 is described in detail as follows:
(2) When IFB pin voltage becomes VIFB(OCL.VR) or more
(see Figure 8-20), the IC switches to Auto Restart 1.
8.7.1 Overcurrent of Boost Converter Part
(OCP)
(3) The LED current increases further and when the IFB
pin voltage increases to the IFB Pin Overcurrent
Protection High Threshold Voltage, VIFB(OCH) = 4.0 V
or more, the IC switches to Auto Restart 2.
When the OC pin detects the overcurrent of boost
circuit, the IC switches to Auto Restart 1.
Figure 8-22 shows the peripheral circuit of OC pin.
When the boost MOSFET (Q1, Q3) turns on, the current
flowing to L1 is detected by the current detection resistor
(R20, R48), and the voltage on R4 is input to the OC pin.
When the OC pin voltage increases to the OC Pin
Overcurrent Protection Threshold Voltage, VOCP = 0.60
V or more, the on-duty becomes narrow by
pulse-by-pulse basis, and the output power is limited.
U1
LED_OUT1(+)
IFB1 5
Feed back1
control
COMP1 4
LED_OUT1(-)
C15
L1
Q2
R42 C16
OC1 control
R15
Output current
detection resistor
LED_OUT1(+)
D1
IL(ON)
LED_OUT1(-)
Q1
C2
R18
R20
Q2
Figure 8-23 The peripheral circuit of IFB pin
and COMP pin
R15
8.7.3 Overvoltage of LED_OUT (+) (OVP)
U1
OC1
6
C3
GND
9
Figure 8-22 OC pin peripheral circuit
8.7.2 Overcurrent of LED Output
(LED_OCP)
Figure 8-23 shows the peripheral circuit of IFB pin
and COMP pin.
When the dimming MOSFET (Q2, Q4) turns on, the
output current is detected by the detection resistor (R15,
R61). When the boost operation cannot be done by
failure such as short circuits in LED string, the IFB pin
voltage is increased by the increase of LED current.
There are three types of operation modes in LED_OCP
state.
The OVP pin detects LED_OUT (+) voltage as shown
in Figure 8-24.
When the LED_OUT (+) or the IFB pin is open and
the OVP pin voltage increases to the OVP Pin
Overvoltage Protection Threshold Voltage, VOVP = 3.00
V, the IC immediately stops switching operation. When
the OVP pin voltage decreases to the OVP Pin
Overvoltage Protection Release Threshold Voltage,
VOVP(OFF) = 2.75 V or the IFB pin voltage decreases to
VIFB(AR.VR) in Figure 8-20, then the IC switches to Auto
Restart 1.
LED_OUT2(+)
D6
C18
LED_OUT1(+)
Q4
D1
D9
D8
R61
C2
R1
R2
(1) When the IFB pin voltage is increased by the increase
of LED current, COMP pin voltage is decreases. In
addition, when the COMP pin voltage decreases to
the COMP Pin Voltage at Oscillation Stop,
VCOMP(OFF) = 0.25 V or less, the IC stops switching
operation, and limits the increase of the output
current.
When IFB pin voltage is decreased by the decrease of
LED current, COMP pin voltage increases. When
COMP pin voltage becomes VCOMP(ON) = 0.50 V or
more, the IC restarts switching operation.
BL0200-DS Rev.2.2
Apr. 04, 2014
U1
R3
OVP
C5
Q2
R15
R4
GND
Figure 8-24 OVP pin peripheral circuit
SANKEN ELECTRIC CO.,LTD.
17
BL0200 Series
8.7.4 Short Mode between LED_OUT(−)
and GND
When the LED_OUT (–) and the GND are shorted,
and the IFB pin voltage decreases to VIFB(AR.VR) in Figure
8-20, then the IC switches to Auto Restart 1.
8.7.5 Short Mode of LED Current Detection
Resistor (RSEN_Short)
When the output current detection resistor (R15, R61),
is shorted, the IFB pin voltage decreases. When the IFB
pin voltage decreases to VIFB(AR.VR) in Figure 8-20, then
the IC switches to Auto Restart 1.
8.7.6 Short Mode of LED Output Both Ends
When the LED_OUT (+) and LED_OUT (–) are
shorted, the short current flows through the output
current detection resistor (R15, R61), while the dimming
MOSFET (Q2, Q4) turns on. The IFB pin detects the
voltage rise of the detection resistor. When the IFB pin
voltage increases to the IFB Pin Overcurrent Protection
High Threshold Voltage, VIFB(OCH) = 4.0 V or more, the
IC switches to Auto Restart 2.
8.7.7 Open Mode of LED Current Detection
Resistor (RSEN_Open)
When the output current detection resistor (R15, R61),
is open, the IFB pin voltage increases. When the IFB pin
voltage increases to the IFB Pin Overcurrent Protection
High Threshold Voltage, VIFB(OCH) = 4.0 V or more, the
IC switches to Auto Restart 2.
8.7.8 Overtemperature of junction of IC
(TSD)
When the temperature of the IC increases to
Tj(TSD) = 125 °C (min) or more, the TSD is activated, and
the IC stops switching operation. When the junction
temperature decreases by Tj(TSD) − Tj(TSD)HYS after the fault
condition is removed, the IC returns to normal operation
automatically.
9. Design Notes
9.1 Peripheral Components
Take care to use the proper rating and proper type of
components.
 Input and output electrolytic capacitors, C1, C2, C18
and C21
▫ Apply proper design margin to accommodate ripple
current, voltage, and temperature rise.
▫ Use of high ripple current and low impedance types,
designed for switch-mode power supplies, is
recommended, depending on their purposes.
 Inductor, L1, L2
▫ Apply proper design margin to temperature rise by
core loss and copper loss.
▫ Apply proper design margin to core saturation.
 Current detection resistors, R15, R20, R48 and R61
Choose a type of low internal inductance because a
high frequency switching current flows to the current
detection resistor, and of properly allowable
dissipation.
9.2 Inductor Design Parameters
The CRM* or DCM* mode of boost converter with
PWM dimming can improve the output current rise
during PWM dimming.
* CRM is the critical conduction mode,
DCM is the discontinuous conduction mode.
(1) On-duty Setting
The output voltage of boost converter is more than
the input voltage. The on-duty, DON can be calculated
using following equation. The equality of the
equation means the condition of CRM mode
operation and the inequality means that of DCM
mode operation.
D ON 
VOUT  VIN
VOUT
(9-1)
where:
VIN is the minimum input voltage,
VOUT is the maximum forward voltage drop of LED
string.
DON is selected by the above equation applied to
CRM or DCM mode. In case fPWM = 100 kHz, the
range of DON should be 3.1 % to 90 %. In case
fPWM = 200 kHz, the range of DON should be 6 % to
90 %. (The minimum value results from the condition
of tMIN, and fPWM. The maximum value is DMAX).
BL0200-DS Rev.2.2
Apr. 04, 2014
SANKEN ELECTRIC CO.,LTD.
18
BL0200 Series
(2) Inductance value, L
The inductance value, L, for DCM or CRM mode can
be calculated as follow:
L
VIN  DON 2
2  I OUT  f PWM  VO UT  VIN 
(9-2)
where:
IOUT is the maximum output current,
fPWM is the maximum operation frequency of PWM
(3) Peak inductor current, ILP
I LP 
VIN  D ON
L  f PWM
(9-3)
(4) Inductor selection
The inductor should be applied the value of
inductance, L, from equation (9-2) and the DC
superimposition characteristics being higher than the
peak inductor current, ILP, from equation (9-3).
9.3 PCD Trace Layout and Component
Placement
Since the PCB circuit trace design and the component
layout significantly affects operation, EMI noise, and
power dissipation, the high frequency PCB trace as shown
in Figure 9-1 should be low impedance with small loop
and wide trace.
L1
D1
C1
C2
Q1
L2
C21
Q3
(1) Main Circuit Trace Layout
This is the main trace containing switching currents,
and thus it should be as wide trace and small loop as
possible.
C1 and C18 should be connected near the inductors,
L1and L2, in order to reduce impedance of the high
frequency current loop.
(2) Control Ground Trace Layout
Since the operation of IC may be affected from the
large current of the main trace that flows in control
ground trace, the control ground trace should be
connected at a single point grounding of point A with
a dedicated trace.
(3) Current Detection Resistor Trace Layout
R15, R20, R48 and R61 are current detection
resistors.
The trace from the base of current detection resistor
should be connected to the pin of IC with a dedicated
trace.
(4) COMP pin Trace Layout for Compensation
Component
The components connected to COMP pin are
compensation components.
The trace of the compensation component should be
connected as close as possible to COMP pin, to
reduce the influence of noise.
(5) Bypass Capacitor Trace Layout on VCC , REG, and
VREF pins
C8, C12 and C10 of bypass capacitors, connected to
VCC, REG, and VREF pins respectively, should be
connected as close as possible to the pin of IC, to
reduce the influence of noise.
D1
C18
Figure 9-1 High-frequency current loops
(hatched areas)
BL0200-DS Rev.2.2
Apr. 04, 2014
In addition, the ground traces affect radiated EMI noise,
and wide, short traces should be taken into account.
Figure 9-2 shows the circuit design example of
BL0200C.
(6) Power MOSFET Gate Trace Layout
The resistor between gate and source, R19, R24, R47
and R63, should be connected near each the gate of
the power MOSFETs and the ground line side of the
current detection resistance.
Peripheral components of MOSFET, gate resistors
and diodes, should be connected as close as possible
between each the gate of the power MOSFETs and
the pin of IC.
SANKEN ELECTRIC CO.,LTD.
19
BL0200 Series
(6) Power MOSFET Gate Trace Layout
Gate-Source resistor should be connected near gate of power MOSFET and ground line side of Current detection resistor.
Gate resistors and diodes should be connected as close as possible between the gate of power MOSFET and the pin of IC.
(1) Main circuit trace Should be
as wide trace and small loop.
LED_OUT2(+)
LED_OUT2(-)
P_IN
D9
L2
F1
D6
LED_OUT1(+)
L1
C21
Q3
R45
Q4
Q1
Q2
C2
D10
D7
R44
R22
R17
C1
A
R47
D2
R61
R49
R19
(2) Control ground trace layout
should be connected at a single
point grounding of point A with
a dedicated trace
R24
R20
R4
R15
R21
C8
R46
(3) Current detection resistance
should be connected to the pin
of IC with a dedicated trace.
R62
R18
VCC
SW2
OC2
IFB2
COMP2
R38
PWM2
ON/OFF
EN
R39
VCC_IN
VREF
9
U1
10
11
8
12
7
13
14
BL0202
DRV2
6
5
15
4
16
3
17
2
18
1
GND
SW1
DRV1
OC1
R23
IFB1
COMP1 R27
PWM1
OVP
REG
C12
R41
C7
R37
C20
R32 R34
R36
S_GND
R1
D3
R16
PWM2_IN
R2
R3
R63
R48
LED_OUT1(-)
D8
R50
C18
D1
C11
C19
C22
C13
C14
C10
C4
R42
R35
R33
C15
C16
C3
C5
C6
R26
R25
PWM1_IN
(5)Bypass capacitor（C8,C10,C12）should be
connected as close as possible to the pin of IC.
(4) COMP pin peripheral components should be
connected as close as possible to the pin of IC.
Figure 9-2 Peripheral circuit example around the IC (BL0200C)
BL0200-DS Rev.2.2
Apr. 04, 2014
SANKEN ELECTRIC CO.,LTD.
20
BL0200 Series
10.Reference Design of Power Supply
As an example, the following show a power supply specification of BL0200C and BL0202B, circuit schematic, bill
of materials, and transformer specification.
This reference design is the example of the value of parts, and should be adjusted based on actual operation in the
application.
10.1 BL0202B
 BL0202B Features
- DRV pin oscillation frequency is 100 kHz
- Enable function
 Power Supply Specification
IC
Input voltage
Maximum output power
Output voltage
Output current
BL0202B
DC 24 V
40 W (max.)
50 V
400 mA × 2
 Circuit
OUT2
F1
D9
P_IN
L2
D6
OUT1
R50
L1
D1
D8
Q4
C21
C18
R22
D10
R45
Q3
R49
Q2
R63
C1
R51 R52 R53 R54 R55
C2
R47
D3
R17
D7
R44
R1
R2
Q1
R21
R48
R61
R56 R57 R58 R59 R60
R16
D2
R19
R3
R5 R6 R7 R8 R9
R24
R15
R20
R4
P_GND
R46
R10 R11 R12 R13 R14
C8
R62
R18
OC2
IFB2
PWM2_IN
COMP2
R38
PWM2
ON/OFF
EN
R39
VREF
9
11
8
12
7
13
14
15
6
5
4
16
3
17
2
18
1
R37
VCC_IN
C19
C7
R41
C11
GND
SW1
DRV1
OC1
R23
IFB1
COMP1
R27
PWM1
OVP
REG
C12
C22
R42
R36
R34
C13
C14
C16
R35
C3
C4
C5
C6
R26
R32
C20
C10
S_GND
BL0202B
SW2
DRV2
10
U1
VCC
R33
C15
R25
PWM1_IN
BL0200-DS Rev.2.2
Apr. 04, 2014
TC_BL0202_3_R1
SANKEN ELECTRIC CO.,LTD.
21
BL0200 Series
 Bill of Materials
Symbol
Part type
Ratings(1)
F1
L1
L2
D1
D2
D3
D6
D7
D8
D10
Fuse
Inductor
Inductor
Fast recovery
Schottky
Schottky
Fast recovery
Schottky
Q1
Power MOSFET
Q2
Power MOSFET
Q3
Power MOSFET
Q4
Power MOSFET
C1
C2
C3
C4
C5
C6
C7
Electrolytic
Electrolytic
Ceramic, chip, 2012
Ceramic, chip, 2012
Ceramic, chip, 2012
Ceramic, chip, 2012
Electrolytic
3A
50 μH, 3 A
50 μH, 3 A
200 V, 1.5 A
30 V, 1 A
30 V, 1 A
200 V, 1.5 A
30 V, 1 A
200 V, 1 A
30 V, 1 A
200 V,
45 mΩ (typ.)
100 V,
1 Ω (typ.)
200 V,
45 mΩ (typ.)
100 V,
1 Ω (typ.)
50 V, 22 μF
100 V, 100 μF
100 pF
100 pF
10 nF
470 pF
50 V, 100 μF
C8
Ceramic, chip, 2012
50 V, 0.1 μF
C9
C10
C11
C12
C13
C14
C15
C16
C18
C19
C20
C21
C22
R1
R2
R3
Ceramic, chip, 2012
Ceramic, chip, 2012
Ceramic, chip, 2012
Ceramic, chip, 2012
Ceramic, chip, 2012
Ceramic, chip, 2012
Ceramic, chip, 2012
Ceramic, chip, 2012
Electrolytic
Ceramic, chip, 2012
Ceramic, chip, 2012
Electrolytic
Ceramic, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
50 V, 0.1 μF
0.1 μF
470 pF
0.1 μF
0.047 μF
2200 pF
0.047 μF
2200 pF
100 V, 100 μF
100 pF
100 pF
50 V, 22 μF
0.1 μF
110 kΩ
110 kΩ
0Ω
Schottky
(2)
(2)
(2)
(2)
(2)
(2)
(2)
(2)
(3)
(3)
(3)
Recommended
Sanken Parts
Symbol
Part type
Ratings(1)
EL 1Z
SJPA-D3
SJPA-D3
EL 1Z
SJPA-D3
AL01Z
SJPA-D3
R4
R5-R14
R15
R16
R17
R18
R19
R20
R21
R22
SKP202
R23
General, chip, 2012
1.5 kΩ
R24
General, chip, 2012
10 kΩ
R25
General, chip, 2012
1 kΩ
R26
General, chip, 2012
33 kΩ
R27
R32
R33
R34
R35
R37
R38
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
10 kΩ
10 kΩ
0Ω
82 kΩ
560 Ω
10 kΩ
1 kΩ
5 kΩ
(VEN = 3.5 V)
10 kΩ
22 kΩ
22 kΩ
10 Ω
100 Ω
100 Ω
10 kΩ
0.22 Ω, 2 W
470 Ω
1.5 kΩ
Open
1.35 Ω, 1 W
1.5 kΩ
10 kΩ
SKP202
(2)
(2)
R39
R40
R41
R42
R44
R45
R46
R47
R48
R49
R50
R51-R60
R61
R62
R63
U1
General, chip, 2012
General, chip, 2012
General
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General
General, chip, 2012
General, chip, 2012
11 kΩ
Open
1.35 Ω, 1 W
10 Ω
100 Ω
100 Ω
10 kΩ
0.22 Ω, 2 W
470 Ω
1.5 kΩ
General, chip, 2012
(2)
(2)
(2)
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General
General, chip, 2012
General, chip, 2012
General, chip, 2012
General
General, chip, 2012
General, chip, 2012
IC
Recommended
Sanken Parts
BL0202B
(1)
Unless otherwise specified, the voltage rating of capacitor is 50V or less, and the power rating of resistor is 1/8W or less.
It is necessary to be adjusted based on actual operation in the application.
(3)
Resistors applied high DC voltage and of high resistance are recommended to select resistors designed against
electromigration or use combinations of resistors in series for that to reduce each applied voltage, according to the
requirement of the application.
(2)
BL0200-DS Rev.2.2
Apr. 04, 2014
SANKEN ELECTRIC CO.,LTD.
22
BL0200 Series
10.2 BL0200C
 BL0200C Features
- DRV pin oscillation frequency is 200 kHz
- Error signal output
 Power Supply Specification
IC
Input voltage
Maximum output power
Output voltage
Output current
BL0200C
DC 24 V
40 W (max.)
50 V
400 mA × 2
 Circuit Schematic
OUT2
F1
D9
P_IN
L2
D6
OUT1
R50
L1
D1
D8
Q4
C21
C18
R22
D10
R45
Q3
R49
Q2
R63
C1
R51 R52 R53 R54 R55
C2
R47
D3
R17
D7
R44
R1
R2
Q1
R21
R48
R61
R56 R57 R58 R59 R60
R16
D2
R19
R3
R5 R6 R7 R8 R9
R24
R15
R20
R4
P_GND
R46
R10 R11 R12 R13 R14
C8
R62
R18
OC2
IFB2
PWM2_IN
COMP2
R38
PWM2
ER_OUT
ER
R39
VREF
Q5
VCC_IN
R28
C9
S_GND
Q6
R30
8
12
7
13
14
15
6
5
4
16
3
17
2
18
1
GND
SW1
DRV1
OC1
R23
IFB1
COMP1
R27
PWM1
OVP
REG
C12
R40
R41
R42
R29
C7
R31
11
R37
C19
ON/OFF
9
BL0200C
SW2
DRV2
10
U1
VCC
C11
R36
R34
C13
C14
C16
R35
C3
C4
C5
C6
R26
R32
C20
C10
R33
C15
R25
PWM1_IN
BL0200-DS Rev.2.2
Apr. 04, 2014
TC_BL0200C_3_R1
SANKEN ELECTRIC CO.,LTD.
23
BL0200 Series
 Bill of Materials
Symbol
Part type
F1
L1
L2
D1
D2
D3
D6
D7
D8
D9
D10
Fuse
Inductor
Inductor
Fast recovery
Schottky
Schottky
Fast recovery
Schottky
Q1
Power MOSFET
Q2
Power MOSFET
Q3
Power MOSFET
Q4
Power MOSFET
Q5
Q6
C1
C2
C3
C4
C5
C6
C7
C8
C9
C10
C11
C12
C13
C14
C15
C16
C18
C19
C20
C21
R1
R2
R3
R4
PNP Transistor
NPN Transistor
Electrolytic
Electrolytic
Ceramic, chip, 2012
Ceramic, chip, 2012
Ceramic, chip, 2012
Ceramic, chip, 2012
Electrolytic
Ceramic, chip, 2012
Ceramic, chip, 2012
Ceramic, chip, 2012
Ceramic, chip, 2012
Ceramic, chip, 2012
Ceramic, chip, 2012
Ceramic, chip, 2012
Ceramic, chip, 2012
Ceramic, chip, 2012
Electrolytic
Ceramic, chip, 2012
Ceramic, chip, 2012
Electrolytic
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
Schottky
(2)
(2)
(2)
(2)
(2)
(2)
(2)
(2)
(3)
(3)
(3)
Ratings(1)
3A
25 μH, 3 A
25 μH, 3 A
200 V, 1.5 A
30 V, 1 A
30 V, 1 A
200 V, 1.5 A
30 V, 1 A
200 V, 1 A
200 V, 1 A
30 V, 1 A
200 V,
45 mΩ (typ.)
100 V,
1 Ω (typ.)
200 V,
45 mΩ (typ.)
100 V,
1 Ω (typ.)
−50 V, 0.1 A
50 V, 0.1 A
50 V, 22 μF
100 V, 47 μF
100 pF
100 pF
10 nF
470 pF
50 V, 100 μF
50 V, 0.1 μF
50 V, 0.1 μF
0.1 μF
470 pF
0.1 μF
0.047 μF
2200 pF
0.047 μF
2200 pF
100 V, 47 μF
100 pF
100 pF
50 V, 22 μF
110 kΩ
110 kΩ
0Ω
11 kΩ
Recommended
Sanken Parts
Symbol
Part type
Ratings(1)
EL 1Z
SJPA-D3
SJPA-D3
EL 1Z
SJPA-D3
AL01Z
AL01Z
SJPA-D3
R5-R14
R15
R16
R17
R18
R19
R20
R21
R22
R23
R24
SKP202
R25
General, chip, 2012
1 kΩ
R26
General, chip, 2012
33 kΩ
R27
General, chip, 2012
10 kΩ
R28
General, chip, 2012
10 kΩ
R29
R30
R31
R32
R33
R34
R35
R36
R37
R38
R39
R40
R41
R42
R44
R45
R46
R47
R48
R49
R50
R51-R60
R61
R62
R63
U1
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General
General, chip, 2012
General, chip, 2012
General, chip, 2012
General
General, chip, 2012
General, chip, 2012
IC
12 kΩ
10 kΩ
15 kΩ
10 kΩ
0Ω
82 kΩ
560 Ω
33 kΩ
10 kΩ
1 kΩ
10 kΩ
10 kΩ
22 kΩ
22 kΩ
10 Ω
100 Ω
100 Ω
10 kΩ
0.22 Ω, 2 W
470 Ω
1.5 kΩ
Open
1.35 Ω, 1 W
1.5 kΩ
10 kΩ
SKP202
(2)
(2)
(2)
(2)
General, chip, 2012
General
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
General
General, chip, 2012
General, chip, 2012
General, chip, 2012
General, chip, 2012
Open
1.35 Ω, 1 W
10 Ω
100 Ω
100 Ω
10 kΩ
0.22 Ω, 2 W
470 Ω
1.5 kΩ
1.5 kΩ
10 kΩ
Recommended
Sanken Parts
BL0200C
(1)
Unless otherwise specified, the voltage rating of capacitor is 50V or less, and the power rating of resistor is 1/8W or less.
It is necessary to be adjusted based on actual operation in the application.
(3)
Resistors applied high DC voltage and of high resistance are recommended to select resistors designed against
electromigration or use combinations of resistors in series for that to reduce each applied voltage, according to the
requirement of the application.
(2)
BL0200-DS Rev.2.2
Apr. 04, 2014
SANKEN ELECTRIC CO.,LTD.
24
BL0200 Series
OPERATING PRECAUTIONS
In the case that you use Sanken products or design your products by using Sanken products, the reliability largely
depends on the degree of derating to be made to the rated values. Derating may be interpreted as a case that an operation
range is set by derating the load from each rated value or surge voltage or noise is considered for derating in order to
assure or improve the reliability. In general, derating factors include electric stresses such as electric voltage, electric
current, electric power etc., environmental stresses such as ambient temperature, humidity etc. and thermal stress caused
due to self-heating of semiconductor products. For these stresses, instantaneous values, maximum values and minimum
values must be taken into consideration. In addition, it should be noted that since power devices or IC’s including power
devices have large self-heating value, the degree of derating of junction temperature affects the reliability significantly.
Because reliability can be affected adversely by improper storage environments and handling methods, please observe
the following cautions.
Cautions for Storage
 Ensure that storage conditions comply with the standard temperature (5 to 35°C) and the standard relative humidity
(around 40 to 75%); avoid storage locations that experience extreme changes in temperature or humidity.
 Avoid locations where dust or harmful gases are present and avoid direct sunlight.
 Reinspect for rust on leads and solderability of the products that have been stored for a long time.
Cautions for Testing and Handling
When tests are carried out during inspection testing and other standard test periods, protect the products from power
surges from the testing device, shorts between the product pins, and wrong connections. Ensure all test parameters are
within the ratings specified by Sanken for the products.
Soldering
 When soldering the products, please be sure to minimize the working time, within the following limits:
• 260 ± 5 °C
10 ± 1 s (Flow, 2 times)
• 380 ± 10 °C 3.5 ± 0.5 s (Soldering iron, 1 time)
Electrostatic Discharge
 When handling the products, the operator must be grounded. Grounded wrist straps worn should have at least 1MΩ
of resistance from the operator to ground to prevent shock hazard, and it should be placed near the operator.
 Workbenches where the products are handled should be grounded and be provided with conductive table and floor
mats.
 When using measuring equipment such as a curve tracer, the equipment should be grounded.
 When soldering the products, the head of soldering irons or the solder bath must be grounded in order to prevent
leak voltages generated by them from being applied to the products.
 The products should always be stored and transported in Sanken shipping containers or conductive containers, or
be wrapped in aluminum foil.
BL0200-DS Rev.2.2
Apr. 04, 2014
SANKEN ELECTRIC CO.,LTD.
25
BL0200 Series
IMPORTANT NOTES
 The contents in this document are subject to changes, for improvement and other purposes, without notice.
Make sure that this is the latest revision of the document before use.
 Application and operation examples described in this document are quoted for the sole purpose of reference
for the use of the products herein and Sanken can assume no responsibility for any infringement of
industrial property rights, intellectual property rights or any other rights of Sanken or any third party which
may result from its use.
 Unless otherwise agreed in writing by Sanken, Sanken makes no warranties of any kind, whether express or
implied, as to the products, including product merchantability, and fitness for a particular purpose and
special environment, and the information, including its accuracy, usefulness, and reliability, included in this
document.
 Although Sanken undertakes to enhance the quality and reliability of its products, the occurrence of failure
and defect of semiconductor products at a certain rate is inevitable. Users of Sanken products are requested
to take, at their own risk, preventative measures including safety design of the equipment or systems
against any possible injury, death, fires or damages to the society due to device failure or malfunction.
 Sanken products listed in this document are designed and intended for the use as components in general
purpose electronic equipment or apparatus (home appliances, office equipment, telecommunication
equipment, measuring equipment, etc.).
When considering the use of Sanken products in the applications where higher reliability is required
(transportation equipment and its control systems, traffic signal control systems or equipment, fire/crime
alarm systems, various safety devices, etc.), and whenever long life expectancy is required even in general
purpose electronic equipment or apparatus, please contact your nearest Sanken sales representative to
discuss, prior to the use of the products herein.
The use of Sanken products without the written consent of Sanken in the applications where extremely high
reliability is required (aerospace equipment, nuclear power control systems, life support systems, etc.) is
strictly prohibited.
 When using the products specified herein by either (i) combining other products or materials therewith or
(ii) physically, chemically or otherwise processing or treating the products, please duly consider all
possible risks that may result from all such uses in advance and proceed therewith at your own
responsibility.
 Anti radioactive ray design is not considered for the products listed herein.
 Sanken assumes no responsibility for any troubles, such as dropping products caused during transportation
out of Sanken’s distribution network.
 The contents in this document must not be transcribed or copied without Sanken’s written consent.
BL0200-DS Rev.2.2
Apr. 04, 2014
SANKEN ELECTRIC CO.,LTD.
26