SG5701 [TGS]
Low Cost Green-Mode PWM Controller for Flyback Converters;型号: | SG5701 |
厂家: | Tiger Electronic Co.,Ltd |
描述: | Low Cost Green-Mode PWM Controller for Flyback Converters |
文件: | 总13页 (文件大小:679K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
Product Specification
Low Cost Green-Mode PWM Controller for Flyback Converters
SG5701
FEATURES
DESCRIPTION
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
Green-Mode PWM
This highly-integrated PWM controller provides
several special enhancements designed to meet the low
standby-power needs of low-power SMPS. To minimize
standby power consumption, the proprietary green-mode
function provides off-time modulation to linearly
decrease the switching frequency under light-load
conditions. This green-mode function enables the power
supply to easily meet even the strictest power
conservation requirements.
Supports the “Blue Angel” Standard
Low Start-up Current (10uA)
Low Operating Current (2mA)
Leading-Edge Blanking
Constant Output Power Limit
Universal Input
Built-in Synchronized Slope Compensation
Current Mode Operation
Cycle-by-cycle Current Limiting
Under Voltage Lockout (UVLO)
Programmable PWM Frequency
Gate Output Voltage Clamped at 17V
Low Cost
The BiCMOS fabrication process enables reducing
the start-up current to 10uA, and the operating current to
2mA. To further improve power conservation, a large
start-up resistance can be used. Built-in synchronized
slope compensation ensures the stability of peak current
mode control. Proprietary internal compensation provides
a constant output power limit over a universal AC input
range (90VAC to 264VAC). Pulse-by-pulse current
limiting ensures safe operation even during short-circuits.
Few External Components Required
Small SOT-26 Package
APPLICATIONS
General-purpose switching mode power supplies and
flyback power converters, such as
To protect the external power MOSFET from being
damaged by supply over voltage, the SG5701’s output
driver is clamped at 17V. SG5701 controllers can be used
to improve the performance and reduce the production
cost of power supplies. The SG5701 is the best choice for
replacing linear and RCC-mode power adapters. It is
available in 8-pin DIP and 6-pin SOT-26 packages.
ꢀ
ꢀ
ꢀ
Battery chargers for cellular phones, cordless phones,
PDAs, digital cameras, and power tools
Power adapters for ink jet printers, video game
consoles, and portable audio players
Open-frame SMPS for TV/DVD standby and other
auxiliary supplies, home appliances, and consumer
electronics
ꢀ
ꢀ
Replacements for linear transformers and RCC
SMPS
PC 5V standby power.
TYPICAL APPLICATION
© System General Corp.
- 1 -
www.sg.com.tw
Mar. 28, 2006
Version 1.0(IAO33.0025.B1)
Product Specification
Low Cost Green-Mode PWM Controller for Flyback Converters
SG5701
MARKING DIAGRAMS
PIN CONFIGURATION
SOT-26
DIP-8
AAE:SG5701
GATE
GND
FB
M: Mask Version
AAEMW
W: Week
VDD
: Lead Free
RI
SENSE
D: D=DIP
P : Z =Lead Free
Null=Regular Package
XXXXXXXX: Wafer Lot
Y: Year
WW: Week
V: Assembly Location
GND
FB
GATE
VDD
SG5701DP
XXXXXXXXYWWV
NC
NC
RI
SENSE
ORDERING INFORMATION
Part Number
SG5701TZ
PWM Frequency
Package
6-Pin SOT-26 (Lead Free)
8-pin DIP-8 (Lead Free)
70kHz
70kHz
SG5701DZ
PIN DESCRIPTIONS
Pin No.
DIP-8 / (SOT-26)
Name
Type
Function
GATE
VDD
NC
1 / (6)
2 / (5)
3
Driver Output The totem-pole output driver for driving the power MOSFET.
Supply
Power supply.
NC pin.
Current sense. This pin senses the voltage across a resistor. When the voltage reaches
the internal threshold, PWM output is disabled. This activates over-current protection.
This pin also provides current amplitude information for current-mode control.
A resistor connected from the RI pin to ground will generate a constant current source for
the SG5701. This current is used to charge an internal capacitor, to determine the
switching frequency. Increasing the resistance will reduce the amplitude of the current
source and reduce the switching frequency. A 95kΩ resistor Ri results in a 50uA constant
current Ii and a 70kHz switching frequency.
SENSE 4 / (4)
Analog Input
Analog
Input/Output
RI
5 / (3)
NC
FB
6
NC pin.
Feedback. The FB pin provides the output voltage regulation signal. It provides feedback
to the internal PWM comparator, so that the PWM comparator can control the duty cycle.
7 / (2)
Analog Input
Supply
GND
8 / (1)
Ground.
© System General Corp.
Version 1.0(IAO33.0025.B1)
- 2 -
www.sg.com.tw
Mar. 28, 2006
Product Specification
Low Cost Green-Mode PWM Controller for Flyback Converters
SG5701
BLOCK DIAGRAM
© System General Corp.
- 3 -
www.sg.com.tw
Mar. 28, 2006
Version 1.0(IAO33.0025.B1)
Product Specification
Low Cost Green-Mode PWM Controller for Flyback Converters
SG5701
ABSOLUTE MAXIMUM RATINGS
Symbol
VDD
Parameter
Value
30
Unit
V
DC Supply Voltage *
VFB
VSENCE
TJ
Input Voltage to FB Pin
Input Voltage to Sense Pin
Operating Junction Temperature
-0.3 to 6 V
-0.3 to 6V
150
V
V
℃
SOT-26
DIP-8
247
478
PD
Power Dissipation at TA=85℃
mW
SOT-26
DIP-8
263
136
-55 to +150
260(+5/-0)
230(+5/-0)
3.0
R
θ
Thermal Resistance (Junction to Air)**
Storage Temperature Range
Peak Reflow Temperature
°C/W
℃
JA
TSTG
TR
Pb free
Pb
°C
ESD Capability, HBM Model
kV
* All voltage values, except differential voltages, are given with respect to the network ground terminal.
**Thermal JA test board size: SOT 18×12×1.6mm/FR4; DIP 40×35×1.6mm/FR4
Stress beyond those listed under “ absolute maximum ratings” may cause permanent damage to the device.
RECOMMENDED OPERATING CONDITIONS
Symbol
VDD
Parameter
Value
≦24
Unit
V
DC Supply Voltage
TA
Operating Ambient Temperature
-30 to +105
℃
ELECTRICAL CHARACTERISTICS (TA = 25°C, VDD=15V)
VDD Section
Symbol
VOP
Parameter
Test Condition
Min.
Typ.
Max.
24
17.3
12.5
30
Unit
V
V
Continuously Operation Voltage
Start Threshold Voltage
Min. Operating Voltage
Startup Current
VTH(ON)
VDD(MIN)
IDD-ST
TA=25°C
TA=25°C
VDD = VDD-ON – 0.10V
VDD = 15V
15.3
10.9
16.3
11.7
10
2
25
V
uA
mA
V
IDD-OP
VDD-CLAMP
Operating Supply Current
VDD Clamp Voltage
5
26.5
24.5
Feedback Input Section
Symbol
IOZ
Parameter
Test Condition
Min.
Typ.
1.3
4.2
Max.
2.0
Unit
mA
V
Zero Duty Cycle Input Current
Open Loop Voltage
VOP
© System General Corp.
- 4 -
www.sg.com.tw
Mar. 28, 2006
Version 1.0(IAO33.0025.B1)
Product Specification
Low Cost Green-Mode PWM Controller for Flyback Converters
SG5701
Current Sense Section
Symbol
ZCS
Parameter
Test Condition
Min.
Typ.
Max.
100
Unit
kΩ
nsec
V
Input Impedance
10
TPD
Delay to Output
60
1.0
0.85
VTH,FLT
VTH,VALLEY
Current Limit Flatten Threshold Voltage
Current Limit Valley Threshold Voltage
0.80
0.90
V
Oscillator Section
Symbol
FOSC
Parameter
Test Condition
RI=95kΩ
RI=95kΩ
Min.
65
Typ.
70
13
Max.
75
15
Unit
kHz
kHz
mA
Frequency
FOSC-GREEN
IG
Green-Mode Frequency
Green-Mode FB Input Current
Green-Mode Start Threshold FB Input Current
In = 0.3mA for a Maximum Duty Cycle
Green-Mode Modulation Slope
Frequency Variation versus VDD Deviation
Frequency Variation versus Temp. Deviation
1.05
IN
0.85
mA
SG
FDY
FDT
RI=95kΩ
VDD=12 to 20V
TA=-30 to 105 ℃
300
0.02
Hz/uA
%
%
2
2
PWM Section
Symbol
DC (MAX)
DC (MIN)
BNK
Parameter
Test Condition
Min.
70
-
Typ.
75
1
Max.
80
2
Unit
%
%
Maximum Duty Cycle
Minimum Duty Cycle
Leading-Edge Blanking Time
200
nsec
Output Section
Symbol
Parameter
Test Condition
VDD=15V, Io=20mA
Min.
Typ.
Max.
1.5
Unit
V
VOL
Output Voltage Low
VOH
TR
TF
Output Voltage High
Rising Time
Falling Time
VDD=15V, Io=20mA
VDD=15V, CL=1nF
VDD=15V, CL=1nF
VDD=20V
8
V
250
60
17
350
150
18
nsec
nsec
V
VCLAMP
Output Clamp Voltage
16
© System General Corp.
- 5 -
www.sg.com.tw
Mar. 28, 2006
Version 1.0(IAO33.0025.B1)
Product Specification
Low Cost Green-Mode PWM Controller for Flyback Converters
SG5701
TYPICAL CHARACTERISTICS
Min. Operating Voltage (VDD(MIN)) vs
Temperature
Start Threshold Voltage (VTH(ON)) vs Temperature
13.0
17.0
16.8
16.6
16.4
16.2
16.0
12.5
12.0
11.5
11.0
10.5
10.0
-40
-25
-10
5
20
35
50
65
80
95
110
125
-40
-25
-10
5
20
35
50
65
80
95
110
125
Temperature (℃)
Temperature (℃)
Start-up Current (IDD-ST) vs Temperature
Operation Current (IDD-OP) vs Temperature
3
2.5
2
20
15
10
5
1.5
1
0
-40
-25
-10
5
20
35
50
65
80
95
110
125
-40
-25
-10
5
20
35
50
65
80
95
110
125
Temperature (℃)
Temperature (℃)
Green-Mode Frequency (FOSC-GREEN) vs
Temperature
Frequency (Fosc) vs Temperature
75
73
71
69
67
65
15
15
14
14
13
13
12
12
11
-40
-25
-10
5
20
35
50
65
80
95
110 125
-40
-25
-10
5
20
35
50
65
80
95
110 125
Temperature (℃)
Temperature (℃)
© System General Corp.
Version 1.0(IAO33.0025.B1)
- 6 -
www.sg.com.tw
Mar. 28, 2006
Product Specification
Low Cost Green-Mode PWM Controller for Flyback Converters
SG5701
Max. Duty Cycle (DCMAX) vs Temperature
V
DD vs IDD
2
80
1.6
1.2
0.8
0.4
0
78
76
74
72
70
-40 -25 -10
5
20
35
50
65
80
95 110 125
5
6
7
8
9
10
11
12
13
14
15
16
17
V
DD (V)
Temperature (℃)
PWM Frequency (FOSC) vs FB
80
70
60
50
40
30
20
10
0
0.8
0.85
0.9
0.95
1
1.05
1.1
1.15
1.2
FB (mA)
© System General Corp.
Version 1.0(IAO33.0025.B1)
- 7 -
www.sg.com.tw
Mar. 28, 2006
Product Specification
Low Cost Green-Mode PWM Controller for Flyback Converters
SG5701
charge-time determines the internal clock speed and the
switching frequency. Increasing the resistance will reduce
the amplitude of the input current and reduce the
switching frequency. A 95kΩ resistor Ri results in a 50uA
constant current Ii and a 70kHz switching frequency. The
relationship between Ri and the switching frequency is:
OPERATION DESCRIPTION
SG5701 devices integrate many useful designs into
one controller for low-power switch-mode power supplies.
The following descriptions highlight some of the features
of the SG5701 series.
6650
RI (kΩ)
f
PWM =
(kHz )
Start-up Current
The range of the oscillation frequency is designed to
be within 50kHz ~ 100kHz.
The start-up current is only 10uA. Low start-up
current allows a start-up resistor with a high resistance
and a low-wattage to supply the start-up power for the
controller. A 1.5 MΩ, 0.25W, start-up resistor and a
10uF/25V VDD hold-up capacitor would be sufficient for
an AC-to-DC power adapter with a wide input range
(100VAC to 240VAC).
Leading-Edge Blanking
Each time the power MOSFET is switched on, a
turn-on spike will inevitably occur at the sense-resistor.
To avoid premature termination of the switching pulse, a
200 nsec leading-edge blanking time is built in.
Conventional RC filtering can therefore be omitted.
During this blanking period, the current-limit comparator
is disabled and it cannot switch off the gate driver.
Operating Current
The operating current has been reduced to 2mA. The
low operating current results in higher efficiency and
reduces the Vcc hold-up capacitance requirement.
Constant Output Power Limit
Green-Mode Operation
When the SENSE voltage across the sense resistor Rs
reaches the threshold voltage (around 1.0V), the output
GATE drive will be turned off following a short
propagation delay tD. This propagation delay will
introduce an additional current proportional to tD*Vin/Lp.
The propagation delay is nearly constant regardless of the
input line voltage VIN. Higher input line voltages will
result in larger additional currents. At high input line
voltages, the output power limit will be higher than at low
input line voltages.
The proprietary green-mode function provides
off-time modulation to linearly decrease the switching
frequency under light-load conditions. On-time is limited
to provide stronger protection against brownouts and
other abnormal conditions. The feedback current, which is
sampled from the voltage feedback loop, is taken as the
reference. Once the feedback current exceeds the
threshold current, the switching frequency starts to
decrease. This green-mode function dramatically reduces
power consumption under light-load and zero-load
conditions. Power supplies using the SG5701 can easily
meet even the strictest regulations regarding standby
power consumption.
To compensate for this output power limit variation
across a wide AC input range, the threshold voltage is
adjusted by adding a positive ramp. This ramp signal rises
from 0.85V to 1.0V, and then flattens out at 1.0V. A
smaller threshold voltage forces the output GATE drive to
terminate earlier. This reduces the total PWM turn-on
time and makes the output power equal to that of low line
input. This proprietary internal compensation ensures a
constant output power limit for a wide AC input voltage
range (90VAC to 264VAC).
Oscillator Operation
A resistor connected from the RI pin to ground will
generate a constant current source for the SG5701. This
current is used to charge an internal capacitor. The
© System General Corp.
- 8 -
www.sg.com.tw
Mar. 28, 2006
Version 1.0(IAO33.0025.B1)
Product Specification
Low Cost Green-Mode PWM Controller for Flyback Converters
SG5701
current limiting. Built-in slope compensation will
improve stability and prevent sub-harmonic oscillations
due to peak-current mode control. The SG5701 has a
synchronized, positively-sloped ramp built-in at each
switching cycle. The slope of the ramp is:
Under Voltage Lockout (UVLO)
The turn-on and turn-off thresholds of the SG5701
are fixed internally at 16.3V/11.7V. During start-up, the
hold-up capacitor must be charged to 16.3V through the
start-up resistor, so that the SG5701 will be enabled. The
hold-up capacitor will continue to supply VDD until power
can be delivered from the auxiliary winding of the main
transformer. VDD must not drop below 11.7V during this
start-up process. This UVLO hysteresis window ensures
that hold-up capacitor will be adequate to supply VDD
during start-up.
0.33× Duty
Duty(max)
Noise Immunity
Noise from the current sense or the control signal can
cause significant pulse width jitter, particularly in
continuous-conduction mode. While slope compensation
helps alleviate these problems, further precautions should
still be taken. Good placement and layout practices should
be followed. Avoiding long PCB traces and component
leads, locating compensation and filter components near
the SG5701, and increasing the power MOS gate
resistance is advised.
Gate Output
The SG5701 BiCMOS output stage is a fast totem
pole gate driver. Cross conduction has been avoided to
minimize heat dissipation, increase efficiency, and
enhance reliability. The output driver is clamped by an
internal 17V Zener diode in order to protect power
MOSFET transistors against undesired over-voltage gate
signals.
Built-in Slope Compensation
The sensed voltage across the current sense resistor
is used for current mode control and pulse-by-pulse
© System General Corp.
- 9 -
www.sg.com.tw
Mar. 28, 2006
Version 1.0(IAO33.0025.B1)
Product Specification
Low Cost Green-Mode PWM Controller for Flyback Converters
SG5701
REFERENCE CIRCUIT
Circuit
L1
F1
1
2
L
BD1
C3
R5
R3
R4
CX1
R1
R2
-
+
+
2
4
C1
C2
D4
T1
L2
2
1
1
2
10
9
1,2
VO
N
D1
Q1
R10
C7
8
5
+
+
C8
C9
D5
U1
GND
R7
1
2
3
6
5
4
1
GATE
FB
VDD
7
3,4
GND
C6
RI
SENSE
R6
D2
R9
R8
1
2
+
R11
C4
U2
R13
R12
4
3
1
2
R14
C10
U3
CY1
1
BOM
Reference
Component
BD 1A/500V
Reference
L2
Component
10uH 6mm
BD1
CX1 (Optional) XC 0.1uF
CY1 (Optional) YC 102P/400V (Y1)
Q1
MOSFET 1A/600V
R 750KΩ 1206
R 47KΩ 1206
R 47Ω 1206
R 4.7Ω 1206
R 100Ω 0805
R 10Ω 1206
R1,R2
R4,R3
R5
R6
R7
R8
R10
R9
R11
R12
R13
R14
T1
C2
C1
C3
C4
C6
C7
C8
C9
C10
D1
D2
D4
D5
F1
EC 10uF/400V 105℃
CC 103P/500V
CC 102P/500V
EC 10u/50V
CC 472P 0805
(Optional) CC 102P/100V 1206
EC 470u/10V 105℃
EC 220u/10V 105℃
CC 222P 0805
(Optional) R 10Ω 1206
R 100KΩ 0805
R 100Ω 1/8W
R 33KΩ 0805
R 33KΩ 1/8W
R 4.7KΩ 0805
EE-16
Diode FRI07
Diode FR102
Diode SB360
(Optional) ZD 6.8V 0.5W
R 1Ω/0.5W
U1
U2
U3
IC SG5848J (Green PWM IC)
PC817
TL431
L1
20mH 6*8mm
© System General Corp.
- 10 -
www.sg.com.tw
Mar. 28, 2006
Version 1.0(IAO33.0025.B1)
Product Specification
Low Cost Green-Mode PWM Controller for Flyback Converters
SG5701
PACKAGE INFORMATION
8 PINS -- DIP (D)
D
Θ
8
5
e
B
E
1
4
L
b1
b
e
Dimensions
Millimeters
Min.
Inches
Min.
Symbol
Typ.
Max.
5.334
Typ.
Max.
0.210
A
A1
A2
b
b1
D
E
E1
e
0.381
3.175
0.015
0.125
3.302
1.524
0.457
9.271
7.620
6.350
2.540
3.302
9.017
7˚
3.429
0.130
0.060
0.018
0.365
0.300
0.250
0.100
0.130
0.355
7˚
0.135
9.017
6.223
10.160
6.477
0.355
0.245
0.400
0.255
L
eB
θ˚
2.921
8.509
0˚
3.810
9.525
15˚
0.115
0.335
0˚
0.150
0.375
15˚
© System General Corp.
- 11 -
www.sg.com.tw
Mar. 28, 2006
Version 1.0(IAO33.0025.B1)
Product Specification
Low Cost Green-Mode PWM Controller for Flyback Converters
SG5701
SOT-26 (S)
D
b
Detail A
6
4
3
c
1
e
e1
θ
1
L
θ
L1
θ
1
Detail A
Dimensions
Millimeters
Min.
Inches
Symbol
Typ.
Max.
1.45
0.15
1.30
0.50
0.22
Min.
Typ.
Max.
A
0.057
0.006
0.051
0.020
0.009
A1
A2
b
0.90
0.30
0.08
1.15
0.036
0.011
0.003
0.045
c
D
E
E1
e
e1
L
L1
L2
R
R1
θ°
θ1°
2.90
2.80
1.60
0.95
1.90
0.45
0.60
0.25
0.114
0.110
0.063
0.037
0.075
0.018
0.024
0.010
0.30
0.60
0.020
0.024
0.10
0.10
0°
0.004
0.004
0°
0.25
8°
15°
0.010
8°
15°
4°
10°
4°
10°
5°
5°
© System General Corp.
Version 1.0(IAO33.0025.B1)
- 12 -
www.sg.com.tw
Mar. 28, 2006
Product Specification
Low Cost Green-Mode PWM Controller for Flyback Converters
SG5701
DISCLAIMERS
LIFE SUPPORT
System General’s products are not designed to be used as components in devices intended to support or sustain
human life. Use of System General’s products in components intended for surgical implant into the body, or other
applications in which failure of System General’s products could create a situation where personal death or injury may
occur, is not authorized without the express written approval of System General’s Chief Executive Officer. System
General will not be held liable for any damages or claims resulting from the use of its products in medical applications.
MILITARY
System General's products are not designed for use in military applications. Use of System General’s products in
military applications is not authorized without the express written approval of System General’s Chief Executive Officer.
System General will not be held liable for any damages or claims resulting from the use of its products in military
applications.
RIGHT TO MAKE CHANGES
System General reserves the right to change this document and/or this product without notice. Customers are advised
to consult their System General sales representative before ordering.
© System General Corp.
- 13 -
www.sg.com.tw
Mar. 28, 2006
Version 1.0(IAO33.0025.B1)
相关型号:
SG5841DY
Green-Mode PWM Controller for Flyback Converter, Programmable Frequency 47KHz ~ 109KHz, 8LD, MDIP, JEDEC MS-001, .300" WIDE, 3540/RAIL
FAIRCHILD
©2020 ICPDF网 联系我们和版权申明