SEMTECH SC4812EVB

SC4812
Current Mode PWM Controller with
Integrated Start-up Circuit and Op Amp
POWER MANAGEMENT
Description
Features
‹
‹
‹
‹
‹
‹
‹
The circuitry of the SC4812 includes an integrated high
voltage start-up circuit suitable for telecom/industrial ‹
voltage applications. It is disabled during regular opera- ‹
The SC4812 is a highly integrated current mode PWM
controller designed for isolated or non-isolated dc-dc converters in telecommunication and data communication
applications. It minimizes the amount of external discrete
components needed and leads to substantial cost and
space saving converter designs.
tion and improves efficiency. Current mode control with
leading-edge blanking simplifies control loop design and
internal ramp compensation circuit stabilizes the current
loop when operating above 50% duty cycle. Internal error amplifier could be used for non-isolated applications.
Wide input range 12V to 90V
High-voltage start-up circuit
Current mode control
Transconductance error amplifier
Leading-edge blanking
Cycle by cycle current limit
Programmable external soft-start
Thermal shutdown
SO-8 package. Fully WEEE and RoHS compliant
Applications
‹
‹
‹
‹
‹
IP phones, PoE
Telecom isolated converters
Off-line isolated power supplies
Instrumentation power supplies
Battery chargers
Typical Application Circuit
Vin
T1
D1
Vout
C1
C2
R1
VCC
2
U1
VIN
1
R2
C4
8
C3
FB
Q1
OUT
7
SC4812
3
COMP
CS
5
C5
4
R3
R4
Revision: February 6, 2007
SS/SHDN
GND
6
R5
C6
1
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SC4812
POWER MANAGEMENT
Pin Configuration
Ordering Information
TOP VIEW
VIN
VCC
FB
OUT
COMP
GND
SS/SHDN
Part Number
Top Mark
P ackag e
SC4812STRT(1)(2)
S C 4812
SO-8
S C 4812E V B
Evaluation Board
Notes:
(1) Only available in tape and reel packaging. A reel
contains 2500 devices.
(2) Lead free product. This product is fully WEEE and RoHS
compliant.
CS
(SO - 8 PIN)
Absolute Maximum Ratings
Exceeding the specifications below may result in permanent damage to the device, or device malfunction. Operation outside of the parameters specified
in the Electrical Characteristics section is not implied. Exposure to Absolute Maximum rated conditions for extended periods of time may affect device
reliability.
Parameter
Symbol
Maximum
Units
Input Voltage
VIN
-0.5 to 100
V
Supply Voltage
V CC
-0.5 to 18
V
Supply Current
ICC
20
mA
-0.5 to 7
V
±1
A
FB, COMP, CS, and SS/SHDN to GND
OUT Peak Current
Continuous Power Dissipation
PD
Internally limited
W
Junction Temperature Range
TJ
-40 to +150
°C
θ JA
105
°C/W
Storage Temperature Range
TSTG
-65 to +150
°C
Lead Temperature (Soldering) 10 Sec.
TLEAD
+300
°C
Thermal Resistance
(1)
Note:
(1) Mounted to 3” x 4.5”, 4 layer FR4 PCB in still air per JESD51 standards.
 2007 Semtech Corp.
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SC4812
POWER MANAGEMENT
Electrical Characteristics
Unless specified: VCC = 12V, a 10uF capacitor connects VCC to GND, VCS = 0, VIN = 48V, a 0.1uF capacitor connects SS/SHDN to GND, OUT = open
circuit, FB = GND, TA = TJ = -40 to +125ºC. Typical values are at TA = 25ºC
Parameter
Test Conditions
Min
Typ
Max
Unit
90
V
Startup/Winding Regulator
VIN Input Voltage Range
VIN Supply Current
VIN Supply Current after Startup
VIN Shutdown Current
VCC Output Voltage
VCC Current Limit
12
VIN = 90V, VCC open, driver switching
5
7.5
mA
VIN = 90V, VCC open, VFB = 3V,
driver not switching
3.5
5
mA
VIN = 90V
50
100
µA
VIN = 90V, VSS/SHDN = 0
250
380
µA
8
V
Power from VIN
6.8
7.4
10% below no load VCC output voltage
12
20
6
6.5
6.7
V
0.8
1
1.4
V
3
7.5
mA
mA
VCC Supply
VCC Turn-on Voltage
Hysteresis
Operating Current
VCC Zener Shunt Voltage
ICC = 10mA
15.25
16.25
17.25
V
close loop
2.44
2.50
2.56
V
VCC = 8V to 14V
2.425
2.575
V
0.8
µA
Error Amplifier
Feedback Input Voltage
Feedback Input Voltage Regulation
Input Bias Current
0.5
Amplifier Transconductance
1000
µmho
Amplifier Source Current
110
µA
Amplifier Sink Current
110
µA
Open Loop Voltage Gain
60
dB
28
mV/µS
PWM Comparator
Slope Compensation
Oscillator
Clock Frequency Range
235
260
285
kHz
Max Duty Cycle
75
80
85
%
 2007 Semtech Corp.
3
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SC4812
POWER MANAGEMENT
Electrical Characteristics (Cont.)
Unless specified: VCC = 12V, a 10uF capacitor connects VCC to GND, VCS = 0, VIN = 48V, a 0.1uF capacitor connects SS/SHDN to GND, OUT = open
circuit, FB = GND, TA = TJ = -40 to +125ºC. Typical values are at TA = 25ºC
Parameter
Test Conditions
Min
Typ
Max
Units
419
465
510
mV
1
µA
Current Limit
CS Threshold Voltage
CS Input Bias Current
0 ≤ V C S ≤ 2V
-1
Propagation Delay to Gate
70
nS
CS Blanking Time
70
nS
Soft Start
SS Source Current
VSS/SHDN = 0
4
SS Sink Current
Shutdown Threshold
6
8
1
µA
mA
VSS/SHDN falling
0.25
0.5
0.6
VSS/SHDN rising
0.61
0.7
0.8
V
Output
Peak Source Current
570
mA
Peak Sink Current
1000
mA
Rise Time
CL = 1nF
45
nS
Fall Time
CL = 1nF
35
nS
Thermal Shutdown Temperature
150
°C
Thermal Hysteresis
25
°C
Thermal Shutdow n
Note:
(1) This device is ESD sensitive. Use of standard ESD handling precautions is required.
 2007 Semtech Corp.
4
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SC4812
POWER MANAGEMENT
Pin Descriptions
Pin #
Pin Name
Pin Function
1
VIN
High voltage startup input. Connect directly to an input voltage between 12 to 90V. Connects
internally to a high voltage linear regulator that generates VCC during startup.
2
FB
Feedback input to the internal transconductance error amplifier. VFB sensed the regulated
output voltage through an external resistor divider.
3
COMP
Internal transconductance error amplifier output. Compensation network of the overall loop is
placed between this pin and GND.
4
SS/SHDN
Soft start timing capacitor connection. Ramp time to full current limit is approximately TBD
ms/nF. This pin is also the reference voltage output. Bypass with a minimum 10nF capacitor
to GND. The device goes into shutdown when VSS_SHDN is pulled below 0.25V.
5
CS
Current sense input. Turns power switch off if VCS rises above 465mV for cycle-by-cycle
current limiting. CS is also the feedback for the current mode controller. CS is connected to
the PWM comparator through a leading edge blanking circuit.
6
GND
Ground.
7
OUT
Gate drive. Drives a high voltage external N-channel power MOSFET.
8
VC C
Supply voltage. Provides power for entire IC. VCC is regulated from VIN during startup. Bypass
VCC with a 10uF tantalum capacitor in parallel with 0.1uF ceramic capacitor to GND.
 2007 Semtech Corp.
5
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SC4812
POWER MANAGEMENT
Block Diagram
7.4V
 2007 Semtech Corp.
6
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SC4812
POWER MANAGEMENT
Application Information
Introduction
The SC4812 is a 8 pin peak current mode controlled
PWM controller for isolated or non-isolated DC-DC
switching power supplies. It features an internal startup
regulator, programmable external soft start and
programmable cycle -by-cycle current limit It operates in
a fixed frequency at 260KHz.
The SC4812 can be applied in a flyback or forward
topology with the input voltage ranging from 36V to 75V.
RS = 0.465V/(1.2xILIM_PRI)
where, ILIM_PRI is the maximum peak primary-side current.
When VCS > 465mV, the power MOSFET turns off after
70nS propagation delay from the switch current reaches
the trip point to the driver.
PWM Comparator and Slope Compensation
The SC4812 runs fixed 260 KHz frequency by an internal
oscillator. At the beginning of each switching cycle, the
OUT pin switches the MOSFET on. the OUT pin switches
off after the 80% maximum duty cycle has been reached,
regardless of the feedback.
Since an artificial slope is required for current-mode
operation when duty cycle is larger than 50%, the SC4812
uses an internal ramp generator for slope compensation.
The internal ramp signal is reset at the beginning of each
cycle and slews at 26mV/µS.
The PWM comparator compares the instantaneous
primary peak current to the feedback error signal through
the opto-coupler, the internal offset and slope
compensation and determine when to turn off the
MOSFET. In steady state operation, the MOSFET turns
off when:
Startup Regulator
The internal startup regulator of the SC4812 makes its
initial startup without a lossy startup resistor or external
startup circuitry to save cost and board space. As input
voltage exceeds 12V, it provides regulated 7.4V to VCC
which is with the maximum turn-on voltage 6.7V.
Soft-Start/Shutdown and VCC Lockout
During power startup, the output voltage has to ramp up
in a controlled manner to avoid overshoot. The SC4812
internal non-inverting terminal to the error amplifier is
connected to the soft-start pin, which forces the internal
2.5V reference to gradually ramp up during power
startup. In a non-isolated application, as the internal error
amplifier is used, output voltage of a converter ramps
up with close loop startup fashion smoothly. In case of
an isolated application in which the internal error amplifier
may not be used, isolated voltage feedback is through
an opto-coupler and connected to the COMP pin. During
power startup, the COMP pin will follow the soft-start pin
voltage through an internal diode.
Soft-start operation begins when SS/SHDN ramps above
0.7V. When soft-start completed, SS/SHDN is regulated
to 2.50V, the internal voltage reference. Pull SS/SHDN
below 0.5V to disable the controller.
Undervoltage lockout shuts down the controller when VCC
is less than 5.5V. The internal startup regulator and the
reference remain on during shutdown.
ILIM_PRI · RS > VOPTO – VOFFSET - VSLOPE
where ILIM_PRI is the current on the primary side through
the MOSFET. VOFFSET is 1.5V internal offset voltage and
VSLOPE is the artificial ramp starting at with slew rate 26mV/
µ S.
When selecting an inductor in a forward-converter or
magnetizing inductance in a flyback-converter, the
following condition must be met to avoid control-loop subharmonic oscillations:
NS K × RS × VO
×
= 26mV / µS
NP
L
Current-Sense
The function of the CS pin is to limit the peak current
through the MOSFET. Current is sensed at CS as a voltage
across a sense resistor between the source of the
MOSFET and GND. An RC filter is recommended to
connect CS to the sense resistor to reduce effect of the
MOSFET turn-on leading edge spike and noise. Select
the current-sense resistor with the following equation:
 2007 Semtech Corp.
where K = 0.5 TO 1, AND NS and NP are the turns of the
main transformer on secondary and primary side
respectively. L is the output inductor on secondary side
in a forward-converter or magnetizing inductance on
secondary side in a flyback-converter.
7
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SC4812
POWER MANAGEMENT
Applications Information (Cont.)
PCB Layout Guideline
PCB layout is very critical, and the following should be
considered to insure proper operation of the SC4812.
High switching currents are present in applications and
their effect on ground plane must be understood and
minimized.
6) The feed back connection between the error amplifier and the FB pin should be kept as short as possible,
and the GND connections should be to the quiet GND
used for the SC4812.
7) If an opto-coupler is used for isolation, quiet primary
and secondary ground planes should be used. The same
precautions should be followed for the primary GND plane
as mentioned in item 5. For the secondary GND plane,
the GND plane method mentioned in item 4 should be
followed.
8) All the noise sensitive components such as VCC bypass capacitor, COMP resistor/capacitor network, current sensing circuitry and feedback circuitry should be
connected as close as possible to the SC4812. The GND
return should be connected to the quiet SC4812 GND
plane.
9) The connection from the OUT of the SC4812 should
be minimized to avoid any stray inductance. If the layout
can not be optimized due to constraints, a small Schottky
diode may be connected from the OUT pin to the ground
directly at the IC. This will clamp excessive negative voltages at the IC.
1) The high power parts of the circuit should be placed
on a board first. A ground plane should be used. Isolated
or semi-isolated areas of the ground plane may be deliberately introduced to constrain ground currents to particular areas, for example the input capacitor and the
main switch FET ground.
2) The loop formed by the Input Capacitor(s) (Cin), the
main transformer and the main switch FET must be kept
as small as possible. This loop contains all the high fast
transient switching current. Connections should be as
wide and as short as possible to minimize loop inductance. Minimizing this loop area will a) reduce EMI, b)
lower ground injection currents, resulting in electrically
“cleaner” grounds for the rest of the system and c)
minimize source ringing, resulting in more reliable gate
switching signals.
3) The connection between FETs and the main transformer should be a wide trace or copper region. It should
be as short as practical. Since this connection has fast
voltage transitions, keeping this connection short will
minimize EMI.
4) The output capacitor(s) (Cout) should be located as
close to the load as possible. Fast transient load currents are supplied by Cout only. Connections between
Cout and the load must be short, wide copper areas to
minimize inductance and resistance.
5) A 0.1uF to 1uF ceramic capacitor should be directly
connected between VCC and GND and a 1uF to 4.7uF.
The SC4812 is best placed over a quiet ground plane
area. Avoid pulse currents in the Cin and the main switch
FET loop flowing in this area. GND should be returned to
the ground plane close to the package and close to the
ground side of (one of) the VCC supply capacitor(s). Under
no circumstances should GND be returned to a ground
inside the Cin and the main switch FET loop. This can be
achieved by making a star connection between the quiet
GND planes that the SC4812 will be connected to and
the noisy high current GND planes connected to the FETs.
 2007 Semtech Corp.
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TP5
GND
36-75V
C12
1nF
3
2
COMP
FB
D3
1N4148WS
2.4K
R11
C5
22uF/100V
C14
0.47uF
U1
TP13
1
VIN
SS/SD
4
8
VCC
OUT
CS
C2
1uF
5
7
3
2
C13
1nF
TP7
TP6
1
D1
1N4148WS
C8
10uF/16V
SC4812
GND
6
9
TP8
100
R10
C9
150pF
R4
330
10
R17
4
5
6
3
4
1
2
9
10
R16
0.5
D2 SL43
C25 2.2nF/630V
TP10
R1 open C1 open
D6 1N4148WS
TP9
R12
0.5
M1
Si3440
TP1
8
7
TP4
T1
PA1269
3
4
C15
open
R18
open
TP11
R21
open
U2
PS2521L-1
R6
2.4K
C3
470uF/6.3V
2
1
U3
SC431L
1
R7
180
C4
470uF/6.3V
2
 2007 Semtech Corp.
3
TP12
C10 15nF
R8
open
C6
1uF
R14
2.0K
R9
3.32K
R15
0
TP2
RTN
3.3V/4A
SC4812
POWER MANAGEMENT
SC4812 Evaluation Board - Schematics( Isolated Flyback )
www.semtech.com
SC4812
POWER MANAGEMENT
SC4812 Evaluation Board - BOM( Isolated Flyback )
Item
Qty.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
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24
25
26
27
 2007 Semtech Corp.
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2
1
1
1
1
1
1
1
1
3
1
1
1
1
1
1
1
1
2
1
2
1
1
1
1
1
Reference
C2,C6
C3,C4
C5
C8
C9
C10
C12
C13
C14
C25
D1,D3,D6
D2
M1
R4
R6
R7
R9
R10
R11
R12,R16
R14
R15,R21
R17
T1
U1
U2
U3
Part/Value
1uF/6.3V
470uF/6.3V
22uF/100V
10uF/16V
150pF
15nF
1nF
1000pF
0.1uF
2.2nF/630V
1N4148WS
SL43
Si3440
330
2.4K
180
3.32K
100
10K
0.5
2.0K
0
10
PA1269
SC4812
PS2521L-1
SC431L
10
Manufacturer
Kemet
Sanyo
Panasonic-ECG
TDK
muRata
Panasonic-ECG
Vishay
Vishay
Vishay
TDK
Vishay
Vishay
Vishay
Vishay
Vishay
Vishay
Vishay
Panasonic-ECG
Vishay
Susumu
Yageo America
Vishay
Yageo America
Pulse Eng.
Semtech
NEC
Semtech
Manufacturer P.N.
C0805C105M9PAC3810
6TPB470M
ECA-2AHG220
C3216X7R1C106MT
GRM2165C2A151JA01
ECJ-2VB1H153K
VJ0805Y102KXXAT
VJ0805Y102KXXAT
VJ0805Y104KXXxx
C3216X7R2J222K
1N4148WS-V-GS08
SL43
SI3440DV-T1-E3
CRCW0805330RFKEA
CRCW08052K40FKEA
CRCW0805180RFKEA
CRCW08053K32FKEA
ERJ-6ENF1000V
CRCW080510K0FK
RL1220S-R50-F
9C08052A2001FKHFT
CRCW08050000ZSTA
9C08052A10R0FKHFT
PA1269
SC4812STRT
PS2521L-1
SC431LCSK
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TP5
GND
36-75V
C15
47nF
R6
1K
C12
1nF
C5
22uF/100V
3
2
COMP
FB
D3
1N4148WS
TP13
1
VIN
C14
0.47uF
SS/SD
4
8
C2
1uF
5
U1
SC4812
CS
7
3
2
1
C13
1nF
TP7
TP6
C8
10uF/16V
OUT
VCC
11
GND
 2007 Semtech Corp.
6
TP12 D1
1N4148WS
100
R10
C9
150pF
R4
330
10
R17
4
5
6
3
4
1
2
R12
0.25
D2 SL43
R1 open C1 open
R16
0.25
9
10
TP4
M1
Si3440
TP1
8
7
T1
PA1269
C3
470uF/6.3V
C4
470uF/6.3V
C6
1uF
R14
1.0K
R9
1.0K
R15
0
TP2
RTN
5V/2.6A
SC4812
POWER MANAGEMENT
SC4812 Evaluation Board - Schematics( Non-Isolated Flyback )
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SC4812
POWER MANAGEMENT
SC4812 Evaluation Board - BOM( Non-Isolated Flyback )
Item
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Qty.
2
2
1
1
1
2
1
1
1
2
1
1
3
2
2
1
1
 2007 Semtech Corp.
Reference
C2,C6
C3,C4
C5
C8
C9
C12, C13
C14
C16
D1, D3
D2
M1
R4
R9, R13, R14
R10,R17
R12,R16
T1
U1
Part/Value
1uF/16V
470uF/6.3V
22uf/100V
10uF/16V
150pF/100V
1nF/16V
0.1uF/16V
47nF/16V
1N4148WS
SL43
Si3440
330
1.0K
100
0.25
PA1260
SC4812
12
Manufacturer
Panasonic-ECG
Sanyo
Panasonic-ECG
TDK
Panasonic-ECG
Vishay
Vishay
Vishay
Vishay
Vishay
Vishay
Vishay
Panasonic-ECG
Vishay
Panasonic-ECG
Pulse
Semtech
Manufacturer P.N.
ECJ-2FB1C105K
6TPB470M
ECA-2AHG220
C3216X7R1C106MT
ECJ-2VC2A151x
VJ0805Y102KXJPW1BC
VJ0805Y104KXJAC
VJ0805Y473KXJxx
1N4148WS-V-GS08
SL43
SI3440DV-T1-E3
CRCW0805330RJNEA
ERJ-6ENF1001V
CRCW0805100RFKxx
ERJ-6BQFR24x
PA1260
SC4812STRT
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GND
TP5
C5
1u,100V
36-75V
C12
1nF
C9
22uF/100V
3
2
COMP
FB
D4
1N4148WS
10K
R11
C7
1u,100V
U1
TP13
D7
MMSZ4699(12V)
1
VIN
CS
OUT
5
7
TP8
TP6
1
R19
C13
1000pF
TP7
C2
1uF
D1
1N4148WS
C8
10uF/16V
TP12
Q1
FMMT618
5.1K
R22
C14 SC4812
0.47uF
SS/SD
4
8
VCC
GND
6
13
TP9
100
R10
10
R17
R12
0.1
open
TP10
C1
R1
open
D6 1N4148WS
Q2
SUM27N20-78
TP4
T1
CTX03-14856
9
8
12
11
C25 2.2nF/630V
2
1
6
5
4
TP1
TP11
3
4
R6
2.4K
U2
PS2521L-1
C15
open
R18
open
2
1
1
U3
SC431
R7
360
C3
D2
MBRB2035CT 470uF/6.3V
L1
4.7uH
2
 2007 Semtech Corp.
3
D3
BY M07-200
3
R8
open
C10 15nF
C6
C4
470uF/6.3V 1uF
R14
1.0K
R9
1.0K
TP3
R15
0
TP2
RTN
5V/10
SC4812
POWER MANAGEMENT
SC4810B Evaluation Board - Schematics( Forward )
www.semtech.com
SC4812
POWER MANAGEMENT
SC4812 Evaluation Board - BOM( Forward )
Item
Qty.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
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25
26
27
28
29
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31
 2007 Semtech Corp.
1
2
2
2
1
1
1
1
1
1
2
1
1
1
1
1
1
2
1
1
2
1
1
1
1
1
1
1
1
1
1
Reference
C9
C2, C6
C3, C4
C5, C7
C8
C10
C12
C13
C14
C25
D1, D6
D2
D3
D7
L1
Q1
Q2
R5, R15
R6
R7
R9, R14
R10
R11
R12
R17
R19
R22
T1
U1
U2
U3
Part/Value
Manufacturer
Manufacturer P. N.
22uf/100V
Panasonic-ECG
ECA2AHG220
1uf/6.3V
Kemet
C0805C105M9PAC3810
470uf,/6.3V
Sanyo
6TPB470M
1uf/100V
10uf/16V
TDK
C3216X7R1C106MT
15nf
Panasonic-ECG
ECJ2VB1H153K
1nf
Vishay
VJ0805Y102KXXAT
1000pf
Vishay
VJ0805Y102KXXAT
0.47uf
TDK
C2012X7R1E474K
2.2nf/630V
TDK
C3216X7R2J222K
1N4148WS
Vishay
1N4148WS-V-GS08
MBRB2035CT
Vishay
MBRB2035CT/31
BYM07-200
Vishay
BYM07-200
MMSZ4699(12V) ON Semiconductor
MMSZ4699T1
4.7uH
Cooper Bussmann
HC2LP-4R7
FMMT618
Zetex
FMMT618TA
SUM27N20-78
Vishay
SUM27N20-78-E3
0 ohm
Vishay
CRCW08050000ZSTA
2.4k ohm
Vishay
CRCW08052K40FKEA
360 ohm
Panasonic-ECG
ERJ6GEYJ361V
1.0k ohm
Panasonic-ECG
ERJ6ENF1001V
100 ohm
Panasonic-ECG
ERJ6ENF1000V
10k ohm
Vishay
CRCW080510K0FK
0.1 ohm
Panasonic-ECG
ERJ1TRSFR10x
10 ohm
Yageo America
9C08052A10R0FKHFT
1 ohm
Panasonic-ECG
ERJ6GEYJ1R0V
5.1k ohm
Panasonic-ECG
ERJ6GEYJ512V
CTX03-14856 Cooper Bussmann
CTX03-14856
SC4812
Semtech
SC4812STRT
PS2521L-1
NEC
PS2521L-1-E3-A
SC431
Semtech
SC431CSK-1.TRT
14
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SC4812
POWER MANAGEMENT
Outline Drawing - SO-8
A
D
e
N
DIM
A
A1
A2
b
c
D
E1
E
e
h
L
L1
N
01
aaa
bbb
ccc
2X E/2
E1 E
1
2
ccc C
2X N/2 TIPS
e/2
B
D
DIMENSIONS
INCHES
MILLIMETERS
MIN NOM MAX MIN NOM MAX
.069
.053
.010
.004
.065
.049
.020
.012
.010
.007
.189 .193 .197
.150 .154 .157
.236 BSC
.050 BSC
.010
.020
.016 .028 .041
(.041)
8
8°
0°
.004
.010
.008
aaa C
SEATING
PLANE
h
A2 A
C
A1
bxN
bbb
1.75
1.35
0.25
0.10
1.65
1.25
0.51
0.31
0.25
0.17
4.80 4.90 5.00
3.80 3.90 4.00
6.00 BSC
1.27 BSC
0.25
0.50
0.40 0.72 1.04
(1.04)
8
8°
0°
0.10
0.25
0.20
h
H
C A-B D
c
GAGE
PLANE
0.25
SEE DETAIL
L
(L1)
A
DETAIL
SIDE VIEW
01
A
NOTES:
1.
CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES).
2. DATUMS -A- AND -B- TO BE DETERMINED AT DATUM PLANE -H3. DIMENSIONS "E1" AND "D" DO NOT INCLUDE MOLD FLASH, PROTRUSIONS
OR GATE BURRS.
4. REFERENCE JEDEC STD MS-012, VARIATION AA.
Land Pattern - SO-8
X
DIM
(C)
G
C
G
P
X
Y
Z
Z
Y
DIMENSIONS
INCHES
MILLIMETERS
(.205)
.118
.050
.024
.087
.291
(5.20)
3.00
1.27
0.60
2.20
7.40
P
NOTES:
1.
THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY.
CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR
COMPANY'S MANUFACTURING GUIDELINES ARE MET.
2. REFERENCE IPC-SM-782A, RLP NO. 300A.
Contact Information
Semtech Corporation
Power Management Products Division
200 Flynn Road, Camarillo, CA 93012
Phone: (805)498-2111 FAX (805)498-3804
 2007 Semtech Corp.
15
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