LLC Current-Resonant Off-Line Switching Controller
SSC3S900 Series
Description
The SSC3S900 series is a controller with SMZ*
method for LLC current resonant switching power
supplies, incorporating a floating drive circuit for a
high-side power MOSFET.
The product includes useful functions such as Standby
mode change, Overload Protection with input voltage
compensation, Automatic Dead Time Adjustment, and
Capacitive Mode Detection. The product realizes high
performance-to-cost power supply system, downsized by
high efficiency and low noise.
*SMZ: Soft-switched Multi-resonant Zero Current
switch, achieved soft switching operation during all
switching periods
Data Sheet
Package
SOP18
Not to scale
Lineup
Product
SSC3S901
SSC3S902
Protection Operation
UVLO / OCP
Auto Restart
Auto Restart
OLP / OVP / TSD
Auto Restart
Latch Shutdown
Features
● Standby Mode Change Function
▫ Output Power at Light Load: P
O
= 100 mW
(P
IN
= 0.27 W, as a reference with discharge resistor
of 1MΩ for across the line capacitor)
▫ Burst operation in standby mode
▫ Soft-on/Soft-off function: reduces audible noise
● Realizing power supply with universal mains input
voltage
● Floating Drive Circuit: drives a high-side power
MOSFET directly
● Soft-start Function
● Capacitive Mode Detection Function
● Reset Detection Function
● Automatic Dead Time Adjustment Function
● Built-in Startup Circuit
● Input Electrolytic Capacitor Discharge Function
● Protections
▫ Brown-In and Brown-Out Function
▫ High-side Driver UVLO
▫ Overcurrent Protection (OCP): Peak drain current
detection, 2-step detection
▫ Overload Protection (OLP) with Input Voltage
Compensation
▫ Overvoltage Protection (OVP)
▫ Thermal Shutdown (TSD)
Application
Switching power supplies for electronic devices such as:
● Digital appliances: LCD television and so forth
● Office automation (OA) equipment: server, multi-
function printer, and so forth
● Industrial apparatus
● Communication facilities
Typical Application
VAC
T1
VOUT1
VSEN
VCC
FB
VSPL
CSS
CL
RC
PL
SB
1
2
3
18
17
16
ST
NC
VGH
VS
VB
NC
REG
VGL
PC2
GND
VOUT2
GND
PC1
4
5
6
7
8
9
SSC3S900
U1
15
14
13
12
11
10
Standby
PC1
PC2
SSC3S900 - DSJ Rev.2.8
SANKEN ELECTRIC CO., LTD.
Sep. 09, 2020
http://www.sanken-ele.co.jp
© SANKEN ELECTRIC CO., LTD. 2013
1
SSC3S900 Series
Contents
Description ------------------------------------------------------------------------------------------------------ 1
Contents --------------------------------------------------------------------------------------------------------- 2
1. Absolute Maximum Ratings----------------------------------------------------------------------------- 3
2. Electrical Characteristics -------------------------------------------------------------------------------- 4
3. Block Diagram --------------------------------------------------------------------------------------------- 7
4. Pin Configuration Definitions--------------------------------------------------------------------------- 7
5. Typical Application --------------------------------------------------------------------------------------- 8
6. Physical Dimensions -------------------------------------------------------------------------------------- 9
7. Marking Diagram ----------------------------------------------------------------------------------------- 9
8. Operational Description ------------------------------------------------------------------------------- 10
8.1 Resonant Circuit Operation --------------------------------------------------------------------- 10
8.2 Startup Operation --------------------------------------------------------------------------------- 13
8.3 Undervoltage Lockout (UVLO) ---------------------------------------------------------------- 13
8.4 Bias Assist Function ------------------------------------------------------------------------------ 13
8.5 Soft Start Function -------------------------------------------------------------------------------- 14
8.6 Minimum and Maximum Switching Frequency Setting ----------------------------------- 14
8.7 High-side Driver ----------------------------------------------------------------------------------- 14
8.8 Constant Voltage Control Operation ---------------------------------------------------------- 15
8.9 Standby Function---------------------------------------------------------------------------------- 15
8.9.1
Standby Mode Changed by External Signal ------------------------------------------- 16
8.9.2
Burst Oscillation Operation --------------------------------------------------------------- 16
8.10 Automatic Dead Time Adjustment Function ------------------------------------------------ 17
8.11 Brown-In and Brown-Out Function ----------------------------------------------------------- 17
8.12 Capacitive Mode Detection Function ---------------------------------------------------------- 18
8.13 Input Electrolytic Capacitor Discharge Function------------------------------------------- 19
8.14 Reset Detection Function ------------------------------------------------------------------------ 19
8.15 Overvoltage Protection (OVP) ------------------------------------------------------------------ 21
8.16 Overcurrent Protection (OCP) ----------------------------------------------------------------- 21
8.17 Overload Protection (OLP) with Input Voltage Compensation -------------------------- 22
8.17.1 Overload Protection (OLP) ---------------------------------------------------------------- 22
8.17.2 OLP Input Voltage Compensation Function------------------------------------------- 24
8.18 Thermal Shutdown (TSD) ----------------------------------------------------------------------- 25
9. Design Notes ---------------------------------------------------------------------------------------------- 26
9.1 External Components ---------------------------------------------------------------------------- 26
9.1.1
Input and output electrolytic capacitors ------------------------------------------------ 26
9.1.2
Resonant transformer ---------------------------------------------------------------------- 26
9.1.3
Current detection resistor, R
OCP
---------------------------------------------------------- 26
9.1.4
Current resonant capacitor, Ci ----------------------------------------------------------- 26
9.1.5
Gate Pin Peripheral Circuit --------------------------------------------------------------- 26
9.2 PCB Trace Layout and Component Placement --------------------------------------------- 26
10. Pattern Layout Example ------------------------------------------------------------------------------- 28
11. Reference Design of Power Supply ------------------------------------------------------------------ 29
Important Notes ---------------------------------------------------------------------------------------------- 32
SSC3S900 - DSJ Rev.2.8
SANKEN ELECTRIC CO., LTD.
Sep. 09, 2020
http://www.sanken-ele.co.jp
© SANKEN ELECTRIC CO., LTD. 2013
2
SSC3S900 Series
1.
Absolute Maximum Ratings
Current polarities are defined as follows: current going into the IC (sinking) is positive current (+); current coming
out of the IC (sourcing) is negative current (−).
Unless otherwise specified, T
A
is 25°C.
Characteristic
Symbol
Pins
Rating
Unit
VSEN Pin Sink Current
Control Part Input Voltage
FB Pin Voltage
VSPL Pin Sink Current
CSS Pin Voltage
CL Pin Voltage
RC Pin Voltage
PL Pin Voltage
SB Pin Sink Current
VGL pin Voltage
REG pin Source Current
Voltage Between VB Pin and VS Pin
VS Pin Voltage
VGH Pin Voltage
ST Pin Voltage
Operating Ambient Temperature
Storage Temperature
I
SEN
V
CC
V
FB
I
SPL
V
CSS
V
CL
V
RC
V
PL
I
SB
V
GL
I
REG
V
B
−V
S
V
S
V
GH
V
ST
T
OP
T
stg
1 − 10
2 − 10
3 − 10
4 − 10
5 − 10
6 − 10
7 − 10
8 − 10
9 − 10
11 − 10
12 − 10
14 − 15
15 − 10
16 − 10
18 − 10
—
—
1.0
−0.3 to 35
−0.3 to 6
1.0
−0.3 to 6
−0.3 to 6
−6 to 6
−0.3 to 6
100
−0.3 to V
REG
+ 0.3
−10.0
−0.3 to 19.2
−1 to 600
V
S
− 0.3 to V
B
+ 0.3
−0.3 to 600
−40 to 85
−40 to 125
mA
V
V
mA
V
V
V
V
μA
V
mA
V
V
V
V
°C
°C
Junction Temperature
T
J
—
150
°C
* Surge voltage withstand (Human body model) of No.14, 15, 16 and 18 is guaranteed 1000V. Other pins are
guaranteed 2000V.
SSC3S900 - DSJ Rev.2.8
SANKEN ELECTRIC CO., LTD.
Sep. 09, 2020
http://www.sanken-ele.co.jp
© SANKEN ELECTRIC CO., LTD. 2013
3
SSC3S900 Series
2.
Electrical Characteristics
Current polarities are defined as follows: current going into the IC (sinking) is positive current (+); current coming
out of the IC (sourcing) is negative current (−).
Unless otherwise specified, T
A
is 25°C, and V
CC
is 19 V.
Characteristic
Symbol
Conditions
Pins
Min. Typ. Max. Unit
Notes
Start Circuit and Circuit Current
Operation Start Voltage
Operation Stop Voltage
Startup Current Biasing Threshold
Voltage*
Circuit Current in Operation
Circuit Current in Non-Operation
Startup Current
VCC Pin Protection Circuit Release
Threshold Voltage
(1)
VCC Pin Latch Protection Circuit
Release Threshold Voltage
(2)
Circuit Current in Protection
Oscillator
Minimum Frequency
Maximum Frequency
Minimum Dead-Time
Maximum Dead-Time
Externally Adjusted Minimum
Frequency
Feedback Control
FB Pin Oscillation Start Threshold
Voltage
FB Pin Oscillation Stop Threshold
Voltage
FB Pin Maximum Source Current
Soft-start
CSS Pin Charging Current
CSS Pin Reset Current
Maximum Frequency in Soft-start
Standby
SB Pin Standby Threshold Voltage
SB Pin Oscillation Start Threshold
Voltage
(1)
(2)
V
CC(ON)
V
CC(OFF)
V
CC(BIAS)
I
CC(ON)
I
CC(OFF)
I
ST
V
CC(P.OFF)
V
CC(L.OFF)
I
CC(P)
V
CC
= 11V
V
CC
= 9V
2 − 10
2 − 10
2 − 10
2 − 10
2 − 10
18 − 10
2 − 10
2 − 10
2 − 10
12.9
9.0
10.1
—
—
3.0
9.0
6.5
—
14.0
9.8
11.0
—
1.0
6.0
9.8
7.8
1.0
15.1
10.6
11.9
10.0
2.0
9.0
10.6
9.0
2.0
V
V
V
mA
mA
mA
V
V
mA
SSC3S901
SSC3S902
f
(MIN)
f
(MAX)
t
d(MIN)
t
d(MAX)
f
(MIN)ADJ
11 – 10
16 − 15
11 – 10
16 − 15
11 – 10
16 − 15
11 – 10
16 − 15
11 – 10
R
CSS
= 30kΩ
16 − 15
3 – 10
3 – 10
V
FB
= 0V
28.5
230
0.20
1.20
70.0
32.0
300
0.35
1.65
74.0
35.5
380
0.50
2.10
78.0
kHz
kHz
µs
µs
kHz
V
FB(ON)
V
FB(OFF)
I
FB(MAX)
0.15
0.05
−300
−120
1.2
400
0.30
0.20
−195
−105
1.8
500
0.45
0.35
−100
−90
2.4
600
V
V
µA
3 – 10
5 – 10
I
CSS(C)
I
CSS(R)
f
(MAX)SS
V
CC
= 9V
µA
mA
kHz
5 – 10
11 – 10
16 − 15
9 – 10
9 – 10
V
SB(STB)
V
SB(ON)
4.5
0.5
5.0
0.6
5.5
0.7
V
V
V
CC(P.OFF)
= V
CC(OFF)
< V
CC(BIAS)
always.
V
CC(L.OFF)
< V
CC(OFF)
< V
CC(BIAS)
always.
SSC3S900 - DSJ Rev.2.8
SANKEN ELECTRIC CO., LTD.
Sep. 09, 2020
http://www.sanken-ele.co.jp
© SANKEN ELECTRIC CO., LTD. 2013
4
SSC3S900 Series
Characteristic
SB Pin Oscillation Stop Threshold
Voltage
SB Pin Clamp Voltage
SB Pin Source Current
SB Pin Sink Current
Symbol
V
SB(OFF)
V
SB(CLAMP)
I
SB(SRC)
I
SB(SNK)
Conditions
Pins
9 – 10
9 – 10
9 – 10
9 – 10
6 – 10
6 – 10
6 – 10
6 – 10
6 – 10
1 – 10
1 – 10
1 – 10
4 – 10
11 – 10
16 − 15
12 – 10
Min.
0.4
6.1
−20
4
Typ.
0.5
6.7
−10
10
Max.
0.6
7.4
−4
20
Unit
V
V
µA
µA
Notes
Overload Protection (OLP) with Input Voltage Compensation
CL Pin Threshold Voltage (1)
CL Pin Threshold Voltage (2)
CL Pin Threshold Voltage (3)
CL Pin Threshold Voltage (4)
CL Pin Source Current
Brown-In and Brown-Out
VSEN Pin Threshold Voltage (On)
VSEN Pin Threshold Voltage (Off)
VSEN Pin Clamp Voltage
VSPL Pin Clamp Voltage
Reset Detection
Maximum Reset Time
Driver Circuit Power Supply
VREG Pin Output Voltage
High-side Driver
High-side Driver Operation Start
Voltage
High-side Driver Operation Stop
Voltage
Driver Circuit
VGL,VGH Pin Source Current 1
V
REG
9.6
10.4
11.2
V
t
RST(MAX)
4.0
5.0
6.0
µs
V
SEN(ON)
V
SEN(OFF)
V
SEN (CLAMP)
V
SPL (CLAMP)
1.248
1.070
10.0
10.0
1.300
1.115
—
—
1.352
1.160
—
—
V
V
V
V
V
CL1
V
CL2
V
CL3
V
CL4
I
CL
V
SPL
= 1V
V
SPL
= 2V
V
SPL
= 4V
V
SPL
= 5V
4.40
3.05
1.60
1.05
−29
4.69
3.43
1.83
1.29
−17
4.88
3.65
2.05
1.55
−5
V
V
V
V
μA
V
BUV(ON)
V
BUV(OFF)
14 – 15
14 – 15
6.3
5.5
7.3
6.4
8.3
7.2
V
V
I
GL(SRC)1
I
GH(SRC)1
I
GL(SNK)1
I
GH(SNK)1
I
GL(SRC)2
I
GH(SRC)2
I
GL(SNK)2
I
GH(SNK)2
VGL,VGH Pin Sink Current 1
VGL,VGH Pin Source Current 2
VGL,VGH Pin Sink Current 2
V
REG
= 10.5V
V
B
= 10.5V
V
GL
= 0V
V
GH
= 0V
V
REG
= 10.5V
V
B
= 10.5V
V
GL
= 10.5V
V
GH
= 10.5V
V
REG
= 12V
V
B
= 12V
V
GL
= 10.5V
V
GH
= 10.5V
V
REG
= 12V
V
B
= 12V
V
GL
= 1.5V
V
GH
= 1.5V
11 – 10
16 − 15
11 – 10
16 − 15
—
– 540
—
A
—
1.50
—
A
11 – 10
−140
16 − 15
11 – 10
16 − 15
−90
−40
mA
140
250
360
mA
Current Resonant and Overcurrent Protection(OCP)
Capacitive Mode Detection Voltage 1
V
RC1
7 – 10
0.02
−0.18
0.10
−0.10
0.18
−0.02
V
V
SSC3S900 - DSJ Rev.2.8
SANKEN ELECTRIC CO., LTD.
Sep. 09, 2020
http://www.sanken-ele.co.jp
© SANKEN ELECTRIC CO., LTD. 2013
5
