EP-85 6 V, 330 mA Low Cost Charger
04-Oct-2005
7.5 Design Spreadsheet
ACDC_LinkSwitch-
LP_091605; Rev.1.0;
Copyright Power
Integrations 2005
INPUT
INFO OUTP UNIT
UT
ACDC_LinkSwitch-LP_091605_Rev1-0.xls; LinkSwitch-LP
Continuous/Discontinuous Flyback Transformer Design
Spreadsheet
ENTER APPLICATION VARIABLES
EP85 Design
VACMIN
VACMAX
fL
VO
90
265
50
Volts
Volts
Hertz
Volts
Minimum AC Input Voltage
Maximum AC Input Voltage
AC Mains Frequency
Output Voltage (main) measured at the end of output cable (For
CV/CC designs enter typical CV tolerance limit)
Power Supply Output Current (For CV/CC designs enter typical
CC tolerance limit)
6.00
IO
0.33
YES
0.05
BIAS
YES
Amps
Constant Voltage / Constant
Current Output
Output Cable Resistance
PO
CVCC Volts
Enter "YES" for CV/CC output. Enter "NO" for CV only output
0.05 Ohms
1.99 Watts
Enter the resistance of the output cable (if used)
Output Power (VO x IO + dissipation in output cable)
Feedback Type
Bias Winding Enter 'BIAS' for Bias winding feedback and 'OPTO' for
Optocoupler feedback
Add Bias Winding
Yes
Enter 'YES' to add a Bias winding. Enter 'NO' to continue
design without a Bias winding. Addition of Bias winding can
lower no load consumption
Clampless design
n
YES
0.70
Clamp
less
Enter 'YES' for a clampless design. Enter 'NO' if an external
clamp circuit is used.
Efficiency Estimate at output terminals. For CV only designs
enter 0.7 if no better data available
Z
tC
0.50
2.80
0.5
Loss Allocation Factor (Secondary side losses / Total losses)
mSecond Bridge Rectifier Conduction Time Estimate
s
CIN
10.00
H
uFarads Input Capacitance
Input Rectification Type
H
Choose H for Half Wave Rectifier and F for Full Wave
Rectification
ENTER LinkSwitch-LP VARIABLES
LinkSwitch-LP
Chosen Device
ILIMITMIN
ILIMITMAX
fSmin
LNK564
LinkSwitch-LP device
LNK564
0.124 Amps
0.146 Amps
93000 Hertz
1665 A^2Hz
Minimum Current Limit
Maximum Current Limit
Minimum Device Switching Frequency
I^2f Minimum value (product of current limit squared and
frequency is trimmed for tighter tolerance)
I^2f typical value (product of current limit squared and
frequency is trimmed for tighter tolerance)
Reflected Output Voltage
LinkSwitch-LP on-state Drain to Source Voltage
Output Winding Diode Forward Voltage Drop
Ripple to Peak Current Ratio (0.9<KRP<1.0 : 1.0<KDP<6.0)
I^2fMIN
I^2fTYP
1850 A^2Hz
VOR
VDS
VD
88.00
88 Volts
10 Volts
0.5 Volts
1.54
KP
ENTER TRANSFORMER CORE/CONSTRUCTION VARIABLES
Core Type
Core
Bobbin
AE
EE16
Suggested smallest commonly available core
PC40EE16-Z
EE16_BOBBIN
Core Effective Cross Sectional Area
Core Effective Path Length
EE16
P/N:
EE16_BOBBIN P/N:
0.192 cm^2
3.5 cm
LE
AL
BW
M
1140 nH/T^2
8.6 mm
Ungapped Core Effective Inductance
Bobbin Physical Winding Width
Safety Margin Width (Half the Primary to Secondary Creepage
Distance)
0 mm
L
2
Number of primary layers
NS
NB
VB
R1
8
8
27
Number of Secondary Turns
Number of Bias winding turns
Bias Winding Voltage
Resistor divider component between bias wiinding and FB pin
of LinkSwitch-LP
21.93 Volts
36.89 k-ohms
Power Integrations
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