EPR-91 Datasheet, PDF (16/36 Pages) Power Integrations, Inc. – Engineering Prototype Report for EP-91 - 12 W Power Supply using

EP-91 12 V, 1 A, Universal Input Supply
7-Feb-2006
8 Transformer Spreadsheet
ACDC_TinySwitch-III
INPUT
_011906; Rev.0.27;
Copyright Power
Integrations 2006
ENTER APPLICATION VARIABLES
VACMIN
85
VACMAX
265
fL
50
VO
12.00
IO
1.00
INFO
Power
n
0.71
Z
0.50
tC
3.00
CIN
28.80
OUTPUT UNIT
ACDC_TinySwitch-III_011906_Rev0-27.xls;
TinySwitch-III Continuous/Discontinuous
Flyback Transformer Design Spreadsheet
Volts
Volts
Hertz
Volts
Amps
12 Watts
mSeconds
28.8 uFarads
EP91 - 12 V, 1 A, Universal Input
Minimum AC Input Voltage
Maximum AC Input Voltage
AC Mains Frequency
Output Voltage (at continuous power)
Power Supply Output Current (corresponding to
peak power)
Continuous Output Power
Efficiency Estimate at output terminals. Unter 0.7 if
no better data available
Z Factor. Ratio of secondary side losses to the total
losses in the power supply. Use 0.5 if no better data
available
Bridge Rectifier Conduction Time Estimate
Input Capacitance
ENTER TinySwitch-III VARIABLES
TinySwitch-III
TNY278
Chosen Device
Chose Configuration
STD
TNY278
TNY278
Standard
Current Limit
ILIMITMIN
ILIMITTYP
ILIMITMAX
fSmin
I^2fmin
VOR
VDS
VD
KP
KP_TRANSIENT
101.00
0.512 Amps
0.550 Amps
0.588 Amps
124000 Hertz
35.937 A^2kHz
101 Volts
10 Volts
0.7 Volts
0.60
0.38
User defined TinySwitch-III
Enter "RED" for reduced current limit (sealed
adapters), "STD" for standard current limt or "INC"
for increased current limit (peak or higher power
applications)
Minimum Current Limit
Maximum Current Limit
Minimum Device Switching Frequency
I^2f (product of current limit squared and frequency
is trimmed for tighter tolerance)
Reflected Output Voltage (VOR < 135 V
Recommended)
TinySwitch-III on-state Drain to Source Voltage
Output Winding Diode Forward Voltage Drop
Ripple to Peak Current Ratio (KP < 6)
Transient Ripple to Peak Current Ratio. Ensure
KP_TRANSIENT > 0.25
ENTER BIAS WINDING VARIABLES
VB
NB
VZOV
22.00 Volts
12.13
28.00 Volts
Bias Winding Voltage
Bias Winding Number of Turns
Over Voltage Protection zener diode.
UVLO VARIABLES
V_UV_TARGET
92
V_UV_ACTUAL
RUV_IDEAL
RUV_ACTUAL
92.00 Volts
92.20 Volts
3.59 Mohms
3.60 Mohms
Target under-voltage threshold, above which the
power supply with start
Typical start-up voltage based on standard value of
RUV_ACTUAL
Calculated value for UV Lockout resistor
Closest standard value of resistor to RUV_IDEAL
ENTER TRANSFORMER CORE/CONSTRUCTION VARIABLES
Core Type
EE25
EE25
Core
EE25
P/N:
Bobbin
EE25_BOBBIN P/N:
AE
0.404 cm^2
LE
7.34 cm
AL
1420 nH/T^2
User-Selected transformer core
PC40EE25-Z
EE25_BOBBIN
Core Effective Cross Sectional Area
Core Effective Path Length
Ungapped Core Effective Inductance
Power Integrations
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