FAIRCHILD SG6846C

SG6846C
Highly Integrated Green-Mode PWM Controller
Features
Description
ƒ
ƒ
ƒ
Low Start-up Current: 8µA
ƒ
PWM Frequency Continuously Decreasing with
Burst Mode at Light Loads
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
VDD Over-Voltage Protection (OVP)
A highly integrated PWM controller, SG6846C provides
several features to enhance the performance of flyback
converters. To minimize standby power consumption, a
proprietary green-mode function provides off-time
modulation to continuously decrease the switching
frequency under light-load conditions. Under zero-load
conditions, the power supply enters burst-mode, which
completely shuts off PWM output. Output restarts just
before the supply voltage drops below the UVLO lower
limit. This green-mode function enables power supplies
to meet international power conservation requirements.
ƒ
ƒ
ƒ
OCP Threshold is Half Peak Current Limit
Low Operating Current: 3.7mA
Peak-current Mode Operation with Cycle-by-cycle
Current Limiting
AC Input Brownout Protection with Hysteresis
Constant Output Power Limit (Full AC Input Range)
Internal Latch Circuit for OVP, OTP, and OCP
Two-level OCP Delay: 110ms
Programmable PWM Frequency with
Frequency Hopping
Feedback Open-loop Protection with 110ms Delay
Soft Start-up Time: 5ms
Applications
General-purpose switch mode power supplies and
flyback power converters, including:
ƒ
ƒ
ƒ
Power Adapters
Open-frame SMPS
SMPS with Surge-current Output, such as for
Printers, Scanners, Motor Drivers
The SG6846C is designed for SMPS with surge-current
output, incorporated with a two-level OCP function.
Besides the cycle-by-cycle current limiting, if the
switching current is higher than OCP threshold and
lasts for 110ms, SG6846C shuts down immediately.
SG6846C also integrates frequency-hopping function
internally, which helps reduce EMI emission of a power
supply with minimum line filters. The built-in
synchronized slope compensation provides proprietary
internal compensation for constant output power limit
over a universal AC input range. The gate output is
clamped at 18V to protect the external MOSFET from
over-voltage damage.
Other protection functions include AC input brownout
protection with hysteresis and VDD over-voltage
protection. For over-temperature protection, an external
NTC thermistor can be applied to sense the ambient
temperature. When OCP, VDD OVP, or OTP are
activated, an internal latch circuit latches off the
controller. The latch resets when VDD supply is removed.
SG6846C is available in 8-pin SOP and DIP packages.
Ordering Information
Part Number
Operating Temperature Range
OCP Latch
Package
SG6846CLSZ
-20 to +85°C
Yes
8-Pin Small Outline Package (SOP)
SG6846CLDZ
-20 to +85°C
Yes
8-Pin Dual Inline Package (DIP)
All standard Fairchild Semiconductor products are RoHS compliant and many are also “GREEN” or going green.
For Fairchild’s definition of “green” please visit: http://www.fairchildsemi.com/company/green/rohs_green.html.
© 2007 Fairchild Semiconductor Corporation
SG6846C • Rev. 1.1.2
www.fairchildsemi.com
SG6846C — Highly Integrated Green-Mode PWM Controller
May 2008
SG6846C — Highly Integrated Green-Mode PWM Controller
Typical Application
Figure 1. Typical Application
Block Diagram
Ri
4
0.9V/0.7V
VDD
VIN
3
Soft
Driver
Over Power Compensation
8
GATE
2
FB
6
SENSE
1.18-0.08 XVIN
Q
VDD -TH-G
VDD
7
Green
Mode
OSC
R
Internal
BIAS
UVLO
S
6V
3R
R
+
16.5V/10.5V
1R
Latch
Slope
Compensation
Blanking
Circuit
23.6V
1R
Debounce
1R
IRT
RT
OCP
Delay
5
1.05V
1.15V
1
GND
Figure 2. Block Diagram
© 2007 Fairchild Semiconductor Corporation
SG6846C • Rev. 1.1.2
www.fairchildsemi.com
2
SG6846C — Highly Integrated Green-Mode PWM Controller
Marking Information
F: L = OCP Latch
T: D = DIP, S = SOP
P : Z = Lead Free +
ROHS Compatible
Null = regular package
XXXXXXXX: Wafer Lot
Y: Year; WW: Week
V: Assembly Location
SG6846CFTP
XXXXXXXXYWWV
Figure 3. Top Mark
Pin Configuration
GND
GATE
FB
VDD
VIN
SENSE
RI
RT
Figure 4. Pin Configuration
Pin Definitions
Pin #
Name
Function
1
GND
Ground
2
FB
Feedback
The signal from the external compensation circuit is fed into this pin. The
PWM duty cycle is determined in response to the signal from this pin and the
current-sense signal from pin 6.
3
VIN
Line-voltage
Detection
Line-voltage detection, used for brownout protection with hysteresis. Constant
output power limit over universal AC input range is also achieved using this
pin. Add a low-pass filter to filter out line ripple on bulk capacitor.
RI
Reference
Setting
A resistor from the RI pin to ground generates a reference current source that
determines the switching frequency. Increasing the resistance reduces the
switching frequency. Using a 26kΩ resistor results in a 65kHz switching
frequency.
RT
Temperature
Detection
For over-temperature protection, an external NTC thermistor is connected
from this pin to the GND pin. The impedance of the NTC decreases at high
temperatures. Once the voltage of the RT pin drops below a threshold, PWM
output is disabled.
4
5
Description
Ground.
6
SENSE
Current Sense
Current sense. The sensed voltage is used for peak-current-mode control and
cycle-by-cycle current limiting. If the switching current is higher than OCP
threshold and lasts for 110ms, SG6846C turns off immediately. This two-level
OCP feature is especially suitable for SMPS with surge current output.
7
VDD
Power Supply
Power supply. If an open-circuit failure occurs in the feedback loop, the
internal protection circuit disables PWM output as long as VDD exceeds a
threshold.
8
GATE
Driver Output
The totem-pole output driver for the power MOSFET. It is internally clamped
below 18V.
© 2007 Fairchild Semiconductor Corporation
SG6846C • Rev. 1.1.2
www.fairchildsemi.com
3
Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be
operable above the recommended operating conditions and stressing the parts to these levels is not recommended.
In addition, extended exposure to stresses above the recommended operating conditions may affect device
reliability. The absolute maximum ratings are stress ratings only. All voltage values, except differential voltages, are
given with respect to GND pin.
Symbol
Parameter
VDD
Supply Voltage
VL
Input Voltage to FB, SENSE, VIN, RT,RI Pin
PD
Power Dissipation at TA<50°C
ΘJC
Thermal Resistance (Junction-to-Case)
TJ
TSTG
TL
ESD
Min.
Max.
Unit
25
V
-0.3
7.0
V
DIP
800
SOP
400
DIP
67.1
SOP
54.4
mW
°C/W
Operating Junction Temperature
-40
+150
°C
Storage Temperature Range
-65
+150
°C
+260
°C
Human Body Model
5.5
kV
Machine Model
250
V
Lead Temperature, Wave Soldering, 10 Seconds
Electrostatic Discharge Capability
Recommended Operating Conditions
The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended
operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not
recommend exceeding them or designing to Absolute Maximum Ratings.
Symbol
TA
Parameter
Operating Ambient Temperature
© 2007 Fairchild Semiconductor Corporation
SG6846C • Rev. 1.1.2
Min.
Max.
Unit
-20
+85
°C
SG6846C — Highly Integrated Green-Mode PWM Controller
Absolute Maximum Ratings
www.fairchildsemi.com
4
VDD = 15V, TA = 25°C, unless noted.
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
20
V
VDD Section
VDD-OP
Continuously Operating Voltage
VDD-ON
Turn-on Threshold Voltage
15.5
16.5
17.5
V
VDD-OFF
Turn-off Voltage
9.5
10.5
11.5
V
VDD-LH
Threshold Voltage for Latch-off Release
3
4
5
V
IDD-ST
Start-up Current
VDD-ON – 0.16V
IDD-OP
Operating Supply Current
GATE Open
8
30
µA
3.7
5.0
mA
22.6
23.6
24.6
V
VDD-OVP
VDD Over-Voltage Protection (Latch off)
tD-VDDOVP
VDD OVP Debounce Time
RI = 26kΩ
60
100
140
µs
VDD OVP Latch-off Holding Current
VDD = 5V
30
50
70
µA
PWM Turn-off Threshold Voltage
0.65
0.70
0.75
V
PWM Turn-on Threshold Voltage
VINOFF+0.1
8
VINOFF+0.2
0
VINOFF+0.2
2
V
1/3.5
1/4.0
1/4.5
V/V
4.0
5.5
7.0
kΩ
IDD-OVP
VIN Section
VIN-OFF
VIN-ON
Feedback Input Section
AV
Input-Voltage to Current-Sense Attenuation
ZFB
Input Impedance
VFBO
FB Pin Open Voltage
VFB-OLP
tD-OLP
6.2
Threshold Voltage of Open-loop Protection
Open-loop Protection Delay Time
RI = 26kΩ
V
4.7
5.2
5.7
V
100
110
120
ms
SG6846C — Highly Integrated Green-Mode PWM Controller
Electrical Characteristics
Current Sense Section
ZSENSE
Input Impedance
tPD
Delay to Output
tLEB
Leading-edge Blanking Time
12
100
270
360
kΩ
250
ns
ns
VSLOPE
Slope Compensation
Duty = DCYMAX
0.30
0.33
0.36
V
VSTH1V
Threshold Voltage for Current Limit
VIN = 1V
1.07
1.10
1.13
V
VSTH3V
Threshold Voltage for Current Limit
VIN = 3V
0.91
0.94
0.97
V
OCP Threshold Voltage for Current Limit
VIN = 1V
0.52
0.55
0.58
V
OCP Threshold Voltage for Current Limit
VIN = 3V
0.44
0.47
0.50
V
Delay Time for Over-Current Protection
RI = 26kΩ
100
110
120
ms
RI = 26kΩ
4.5
5.0
5.5
ms
RI = 13kΩ
2.25
2.50
2.75
ms
VSTH1V-1/2
VSTH3V-1/2
tD-OCP
tSS-65KHz
tSS-130KHz
Period During Start up Time
Continued on following page…
© 2007 Fairchild Semiconductor Corporation
SG6846C • Rev. 1.1.2
www.fairchildsemi.com
5
VDD = 15V, TA = 25°C, unless noted.
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
62
65
68
±3.7
±4.2
±4.7
124
130
136
±7.4
±8.4
±9.4
44.8
47.0
49.2
±2.54
±2.90
±3.26
Unit
Oscillator Section
fOSC
Normal PWM Frequency
Center
Frequency
RI = 26kΩ, VFB>VN
Jitter Range
fOSC,MAX
Maximum PWM
Frequency
Center
Frequency
RI = 13kΩ, VFB>VN
Jitter Range
kHz
kHz
Center
Minimum PWM Frequency Frequency
Jitter Range
RI = 36kΩ, VFB>VN
thop-1
Jitter Period
RI = 26kΩ, VFB ≥ VN
3.9
4.4
4.9
ms
thop-3
Jitter period
RI = 26kΩ, VFB = VG
10.2
11.5
12.8
ms
fOSC-G
Green-mode Minimum Frequency
RI = 26kΩ
18.0
22.5
25.0
kHz
VFB-N
Pin, FB voltage
FB Pin Frequency
Reduction Threshold Jitter Range
RI = 26kΩ, VFB = VN
VFB-G
FB Voltage at fOSC-G
fOSC,MIN
Pin, FB voltage
RI = 26kΩ, VFB = VG
Jitter Range
SG
Slope for Green-Mode Modulation
RI = 26kΩ
fDV
Frequency Variation vs. VDD Deviation
VDD = 11.5V to 20V
fDT
Frequency Variation vs. Temperature
Deviation
TA = -30 to 85°C
kHz
1.9
2.1
2.3
V
3.7
4.2
4.7
KHz
1.4
1.6
1.8
V
1.27
1.45
1.62
85
1.5
KHz
Hz/mV
5
%
5.0
%
SG6846C — Highly Integrated Green-Mode PWM Controller
Electrical Characteristics (Continued)
Continued on following page…
Figure 5. PWM Frequency
© 2007 Fairchild Semiconductor Corporation
SG6846C • Rev. 1.1.2
www.fairchildsemi.com
6
VDD = 15V, TA = 25°C, unless noted.
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
80
85
90
%
1.5
V
PWM Output Section
DCYMAX
Maximum Duty Cycle
VOL
Output Voltage Low
VDD = 15V, IO = 50mA
VOH
Output Voltage High
VDD = 12V, IO = 50mA
tR
Rising Time
GATE = 1nF
350
tF
Falling Time
GATE = 1nF
50
Gate Output Clamping Voltage
VDD = 20V
VCLAMP
8
V
ns
ns
18
V
(1)
Over-Temperature Protection (OTP) Section
IRT
VRTTH
tDOTP-LATCH
RRT-OFF
Output Current of RT Pin
RI = 26kΩ
Threshold Voltage for OTP
Over-Temperature Latch-off Debounce
RI = 26kΩ
(1)
RI = 26kΩ
Equivalent Impedance of RT for OTP
64
70
76
µA
1.00
1.05
1.10
V
100
14
15
µs
16
kΩ
36
kΩ
RI Section
RINOR
RI Operating Range
13
RIMAX
Maximum RI Value for Protection
10
RIMIN
Minimum RI Value for Protection
MΩ
6
Note:
1. The relationship between RRT-OFF and RI is: RRT -OFF = VOTP-LATCH-OFF / IRT = VRT / (70 μA × 26 / RI (KΩ ))
© 2007 Fairchild Semiconductor Corporation
SG6846C • Rev. 1.1.2
kΩ
(1)
SG6846C — Highly Integrated Green-Mode PWM Controller
Electrical Characteristics (Continued)
www.fairchildsemi.com
7
T urn-o n T hres hold V ol t age (V D D - O N ) v s
T urn-of f V ol t age (V D D - O F F ) v s T em perat ure
T em perat ure
17.0
11.5
11.0
V D D - O F F (V )
V D D -ON (V )
16.8
16.6
16.4
16.2
10.0
9.5
16.0
9.0
-40
-25
-10
5
20
35
50
65
T em perat ure (℃ )
80
95
110
125
-40
Figure 6. Turn-on Threshold Voltage (VDD-ON)
vs. Temperature
-25
-10
5
20
35
50
65
T em perat ure (℃ )
80
95
110
125
Figure 7. Turn-off Threshold Voltage (VDD-OFF)
vs. Temperature
Operating Supply Current (IDD-op) vs Tem perature
S t a rt -Up Curre nt (I D D - S T ) v s T e m p erat ure
4.0
26.0
22.0
IDD -ST (uA )
IDD-op (mA)
3.5
18.0
14.0
3.0
2.5
10.0
6.0
2.0
-40
-25
-10
5
20
35
50
65
80
95
110
125
-40
T em pera t ure (℃ )
-10
5
20
35
50
65
80
95
110
125
Figure 9. Operating Supply Current (IDD-OP)
vs. Temperature
OCP Threshold Voltage for Current Limit (VSTH1V1/[email protected] VIN=1V) vs Temperature
0.60
-25
Temperature (℃ )
Figure 8. Start-up Current (IDD-ST) vs. Temperature
OCP Threshold Voltage for Current Limit (VSTH3V-1/[email protected]=3V) vs Temperature
0.50
0.58
0.49
0.56
VSTH3V-1/2
VSTH1V-1/2
10.5
SG6846C — Highly Integrated Green-Mode PWM Controller
Typical Performance Characteristics
0.54
0.48
0.47
0.52
0.50
0.46
-40
-25
-10
5
20
35
50
65
80
95
110
125
-40
Figure 10. OCP Threshold Voltage for Current Limit
(VSTH1V-1/2 at VIN = 1V) vs. Temperature
© 2007 Fairchild Semiconductor Corporation
SG6846C • Rev. 1.1.2
-25
-10
5
20
35
50
65
80
95
110
125
Temperature (℃ )
Temperature (℃ )
Figure 11. OCP Threshold Voltage for Current Limit
(VSTH3V-1/2 at VIN = 3V) vs. Temperature
www.fairchildsemi.com
8
Maximum Duty Cycle (DCYmax) vs Temperature
Norm al P W M F requenc y (F O S C ) v s T em perat ure
87.0
65.0
86.8
DCYmax (%)
FOSC ( k H z )
64.8
64.6
64.4
64.2
86.6
86.4
86.2
64.0
86.0
-40
-25
-10
5
20
35
50
65
80
95
110
125
-40
-25
-10
5
20
Te m p e r a tu re ( ℃ )
Figure 12. Normal PWM Frequency (fOSC)
vs. Temperature
50
65
80
95
110
125
Figure 13. Maximum Duty Cycle (DCYMAX)
vs. Temperature
O u tp u t C u r r e n t o f R T P i n ( I R T ) v s Te m p e r a tu r e
F B O u t pu t Hi g h V o l t a ge (V R T T H ) v s T em pe ra t u re
1.10
69.8
1.08
VRTTH ( V )
70.0
IRT ( u A )
69.6
69.4
69.2
1.06
1.04
1.02
69.0
1.00
-40
-25
-10
5
20
35
50
65
80
95
110
125
-40
Te m p e r a tu r e ( ℃ )
-25
-10
5
20
35
50
65
T e m p e r a tu r e ( ℃ )
80
95
110
Figure 14. Output Current of RT Pin (IRT)
vs. Temperature
Figure 15. FB Output High Voltage (VRTTH)
vs. Temperature
P W M T urn-o n T hres ho ld V olt a ge (V IN - O N ) v s
P W M T urn-of f T hres hol d V ol t age (V IN - O F F ) v s
T em perat u re
0.910
125
T em perat ure
0.700
0.695
VIN-OFF ( V )
0.905
V IN-ON (V )
35
Temperature (℃ )
SG6846C — Highly Integrated Green-Mode PWM Controller
Typical Performance Characteristics (Continued)
0.900
0.895
0.690
0.685
0.890
0.680
-40
-25
-10
5
20
35
50
65
80
95
110
125
-40
T em perat u re (℃ )
Figure 16. PWM Turn-on Threshold Voltage (VIN-ON)
vs. Temperature
© 2007 Fairchild Semiconductor Corporation
SG6846C • Rev. 1.1.2
-25
-10
5
20
35
50
65
T em perat ure (℃ )
80
95
110
125
Figure 17. PWM Turn-off Threshold Voltage (VIN-OFF)
vs. Temperature
www.fairchildsemi.com
9
Start-up Operation
Two-level Over-current Protection (OCP)
The turn-on/turn-off thresholds are fixed internally at
16.5V/10.5V. To enable the SG6846C during start-up,
the hold-up capacitor must first be charged to 16.5V
through the start-up resistor.
The cycle-by-cycle current limiting shuts down the PWM
immediately when the switching current is over the
peak-current threshold. Additionally, when the switching
current is higher than half of the peak-current threshold,
the internal counter counts down. When the total
accumulated counting time is more than ~110ms
(RI = 26kΩ), the controller is latched off and the internal
counter counts up. When the switching current is lower
than half of the peak current threshold, the internal
counter will count down. When the total accumulated
counting time is more than ~110ms (RI = 26kΩ), the
controller is latched off.
The hold-up capacitor continues to supply VDD before
energy can be delivered from the auxiliary winding of
the main transformer. The VDD must not drop below
10.5V during this start-up process. This UVLO
hysteresis window ensures that the hold-up capacitor
can adequately supply VDD during start-up.
The typical start-up current is only 8µA, which allows a
high-resistance, low-wattage start-up resistor to be used
to minimize power loss. A 1.5MΩ/0.25W start-up
resistor and a 10µF/25V VDD hold-up capacitor are
sufficient for a universal input range.
This two-level OCP protection and up/down counter are
especially designed for SMPS with surge current output,
such as those for printers, scanners, and motor drivers.
The required operating current has been reduced to
3.7mA, which enables higher efficiency and reduces the
VDD hold-up capacitance requirement.
Constant Output Power Limit
For constant output power limit over a universal inputvoltage range, the peak-current threshold is adjusted by
the voltage of the VIN pin. Since the VIN pin is
connected to the rectified AC input line voltage through
the resistive divider, a higher line voltage generates a
higher VIN voltage. The threshold voltage decreases as
the VIN increases, making the maximum output power at
high line input voltage equal to that at low line input.
The value of R-C network should not be so large it
affects the power limit (shown in Figure 18). R and C
should put on less than 300Ω and 1000pF respectively.
Green-Mode Operation
The proprietary green-mode function provides off-time
modulation to continuously decrease the switching
frequency under light-load conditions. Maximum on-time
is limited to provide protection against abnormal
conditions. To further reduce power consumption under
zero-load condition, the PWM oscillator is completely
turned off and the power supply enters burst-mode. This
green-mode function dramatically reduces power
consumption under light-load and zero-load conditions.
Power supplies using the SG6846C can meet even the
most restrictive international regulations regarding
standby power consumption.
Brownout Protection
Since the VIN pin is connected through a resistive
divider to the rectified AC input line voltage, it can also
be used for brownout protection. If the VIN voltage is
less than 0.7V, the PWM output is shut off. As the VIN
over 0.9V, the PWM output is turned on again. The
hysteresis window for ON/OFF is ~0.2V.
Oscillator Operation
A resistor connected from the RI pin to GND generates
a reference current source, inside the SG6846C, used
to determine the PWM frequency. Increasing the
resistance decreases the amplitude of the current
source and reduces the PWM frequency. Using a 26kΩ
resistor results in a corresponding 65kHz switching
frequency. The relationship between RI and the
switching frequency is:
fPWM(kHz) =
1690
R I (kΩ )
VDD Over-voltage Protection (OVP)
VDD over-voltage protection is built in to prevent
damage. When VDD is over 23.6V, the SG6846C is
latched off.
Over-temperature Protection (OTP)
(2)
An external NTC thermistor can be connected from the
RT pin to GND. The impedance of the NTC decreases
at high temperatures. When the voltage of the RT pin
drops below 1.05V, the SG6846C is turned off. For
protection-mode options, see Ordering Information.
If an open-circuit or short-circuit to ground occurs at the
RI pin, the internal protection circuit immediately shuts
down the controller.
© 2007 Fairchild Semiconductor Corporation
SG6846C • Rev. 1.1.2
SG6846C — Highly Integrated Green-Mode PWM Controller
Operation Description
www.fairchildsemi.com
10
Noise Immunity
Noise from the current sense or the control signal may
cause significant pulse-width jitter, particularly in
continuous-conduction mode. Slope compensation
helps alleviate this problem. Good placement and
layout practices should be followed. Avoid long PCB
traces and component leads. Compensation and filter
components should be located near the SG6846C.
Figure 18. Current Sense R-C Filter
© 2007 Fairchild Semiconductor Corporation
SG6846C • Rev. 1.1.2
SG6846C — Highly Integrated Green-Mode PWM Controller
Operation Description (Continued)
www.fairchildsemi.com
11
RT1
R16
D4
2
4
1
5
2
32V
C13
11
C11
12
2
P16V
P16V L2
1
2
2
R11
C5
3
C17+
C14
+
16V 16V
C15
+
1
1
C3
2
R17
2
+
1
9
3
2
+
32V
+
2
1
21
2
1
R4
7
1
1
2
D3
L4
C12
+
10
D2
D1
2
2
6
R9
R3
C16+
3
R12 C4
C2
3
2
R2
R1
13
1
+
R8
1
P7
P32V
P32V L1
1
2
CX2
4
3
1
P2
TX1
1
VZ1
LF1 CY2
BD1
1
CX1LF2
3
4
2
CY1
1
F1
t
P1
2
U1
FB
GATE
Q1
R13
8
1
2
GND
3
1
2
FB
VDD
VIN
SENSE
7
L3
R6
6
1
2
3
1
D5
+
1
C1
R5
4
RI
RT
5
R10
C6
R14
NTC1
R7
P16V
P16V
1
4
R15
FB
P16V
FB
C7
K
R18
P32V
R19
R20
2
3
U2
P32V
P16V
C9
R
R21
A
U3
Figure 19. Application Circuit for 32V / 16V Output
SG6846C — Highly Integrated Green-Mode PWM Controller
Reference Circuit
BOM
Part No.
Value
Part No.
Value
Part No.
Value
R1, R2, R3, R4
470KΩ +/-5%
C4
103 P 630V
D3
FR103 1.0A 200V
R8, R9
S1MΩ +/-1%
C10,C11
102 P 1KV
BD1
DBL406G
R5
16K2Ω +/-1%
C6,C7
102 P 50V
D4
BYT28-300
R15
1K5Ω +/-5%
C9
222 P 50V
D5
BYV32-150
R13
10Ω +/-5%
C14,C17
470µ 25V
F1
250V4A QUICK
R18
4K7Ω +/-5%
C15
220µ 25V
L1,L2
1.8µH
R21
15KΩ +/-1%
C13,C16
220µ 50V
L4
10µH
R7
27KΩ +/-5%
C2
150µ 400V
U3
TL431 +/-1%
R6
330Ω +/-1%
C1
4µ7 50V
U1
SG 6846
R19
102KΩ +/-1%
C3
10µ 50V
U2
PC817
R14
0Ω22 +/-5%
CX1
X1 0.47µ 275V
Q1
7NB60
R16, R17
1W 20Ω +/-5%
C8
Y2 222P 250V
TX1
EI-33
R11
20KΩ +/-5%
C5
100µ 50V
RT1
SCK053
R12
100KΩ +/-5%
CX2
X2 0.1µF 275V
VZ1
14ψ 470V
R20
887KΩ +/-1%
D1
1N4148
R22
10KΩ +/-1%
D2
BYV95C
© 2007 Fairchild Semiconductor Corporation
SG6846C • Rev. 1.1.2
www.fairchildsemi.com
12
SG6846C — Highly Integrated Green-Mode PWM Controller
Physical Dimensions
D
Θ¢X
5
E1
8
B
A
A2
4
A1
1
e
E
L
b1
b
e
Figure 20. 8-Pin DIP
Symbol
Millimeter
Min.
Inch
Typ.
A
Max.
Min.
Typ.
5.334
A1
0.381
A2
3.175
0.210
0.015
3.302
3.429
0.125
0.130
b
1.524
0.060
b1
0.457
0.018
D
9.017
E
E1
9.271
10.160
0.355
7.620
6.223
e
Max.
6.350
0.365
0.135
0.400
0.300
6.477
0.245
2.540
0.250
0.255
0.100
L
2.921
3.302
3.810
0.115
0.130
0.150
eB
8.509
9.017
9.525
0.335
0.355
0.375
θ°
0°
7°
15°
0°
7°
15°
Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner
without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify
or obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions, specifically
the warranty therein, which covers Fairchild products.
Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings:
http://www.fairchildsemi.com/packaging/
© 2007 Fairchild Semiconductor Corporation
SG6846C • Rev. 1.1.2
www.fairchildsemi.com
13
SG6846C — Highly Integrated Green-Mode PWM Controller
Physical Dimensions
8
C
5
E
H
F
1
4
b
e
D
Θ
A1
L
A
Figure 21. 8-Pin SOP
Symbol
Millimeter
Min.
Inch
Typ.
Max.
Min.
Typ.
Max.
A
1.346
1.752
0.053
0.069
A1
0.101
0.254
0.004
0.010
b
0.406
0.016
c
0.203
0.008
D
4.648
E
3.810
e
1.016
1.270
4.978
0.183
3.987
0.150
1.524
0.040
0.157
0.050
0.060
0.015X45°
0.381X45°
F
0.196
H
5.791
6.197
0.228
0.244
L
0.406
1.270
0.016
0.050
θ˚
0°
8°
0°
8°
Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner
without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify
or obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions, specifically
the warranty therein, which covers Fairchild products.
Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings:
http://www.fairchildsemi.com/packaging/
© 2007 Fairchild Semiconductor Corporation
SG6846C • Rev. 1.1.2
www.fairchildsemi.com
14
SG6846C — Highly Integrated Green-Mode PWM Controller
© 2007 Fairchild Semiconductor Corporation
SG6846C • Rev. 1.1.2
www.fairchildsemi.com
15