78253J Series
MAX253 Compatible Converter SM Transformers
Technical enquiries email: mk@murata-ps.com, tel: +44 (0)1908 615232
2014-06-10 KMP_78253JC_A03 Page 1 of 5
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FEATURES
n J-STD-020D reflow
n RoHS compliant
n Maxim MAX253 compatible
n 3.3V and 5V versions
n Isolation to 4kVDC
n Frequency range to 500kHz
n Toroidal construction
n Industry-standard pinout
n UL 94 V-0 package materials
n Low profile
n Industrial temperature range
DESCRIPTION
The 78253 series of converter transformers are
specifically designed for use with the MAX253
chip set to provide isolated power supplies. The
5V input version can supply 1W and the 3.3V
input version can supply 500mW. A centre tapped
secondary winding allows for full bridge, half
bridge or voltage doubling.
For through hole versions see 78253 series
datasheet.
SELECTION GUIDE
Order Code
Input Voltage
Output
Voltage
Max. Output
Current
Isolation
Voltage
Turns
Ratio
V V mA VDC
78253/35JC 3.3 5.0 100 1500 1:2.27
78253/55JC 5.0 5.0 200 1500 1:1.31
78253/35JVC 3.3 5.0 100 4000 1:2.14
78253/55JVC 5.0 5.0 200 4000 1:1.33
ORDER CODE DETAILS
Order Code Package Type Packaging Type Quantity
78253/XXJ(V)C 6 Pin SM Tube 50
78253/XXJ(V)C-R 6 Pin SM Tape & Reel 500
78253/35JC CHARACTERISTICS
Parameter Conditions Min. Typ. Max. Units
Primary Inductance, L
P
100kHz, 250mV 0.27 0.36 0.50 mH
Secondary Inductance, L
S
100kHz, 250mV 1.60 2.00 2.40 mH
Leakage Inductance, L
L
100kHz, 250mV 0.32 1.00 μH
Interwinding Capacitance, C
WW
100kHz, 250mV 24 50 pF
Primary D.C. Resistance, R
DC
>0.1VDC 0.5 1.00
Ω
Volt-time Product, Et Pins 1/2 or 2/3 30 49 Vμs
78253/55JC CHARACTERISTICS
Parameter Conditions Min. Typ. Max. Units
Primary Inductance, L
P
100kHz, 250mV 0.57 0.83 1.10 mH
Secondary Inductance, L
S
100kHz, 250mV 1.10 1.40 1.70 mH
Leakage Inductance, L
L
100kHz, 250mV 0.51 1.00 μH
Interwinding Capacitance, C
WW
100kHz, 250mV 30 50 pF
Primary D.C. Resistance, R
DC
>0.1VDC 0.70 1.50
Ω
Volt-time Product, Et Pins 1/2 or 2/3 40 70 Vμs
78253/35JVC CHARACTERISTICS
Parameter Conditions Min. Typ. Max. Units
Primary Inductance, L
P
100kHz, 20mV 110 142 203 μH
Secondary Inductance, L
S
100kHz, 20mV 550 710 850 μH
Leakage Inductance, L
L
100kHz, 250mV 3.46 5.00 μH
Interwinding Capacitance, C
WW
100kHz, 250mV 2 8.00 pF
Primary D.C. Resistance, R
DC
>0.1VDC 0.30 0.50
Ω
Volt-time Product, Et Pins 1/2 or 2/3 18 30 Vμs
78253/55JVC CHARACTERISTICS
Parameter Conditions Min. Typ. Max. Units
Primary Inductance, L
P
100kHz, 20mV 170 240 335 μH
Secondary Inductance, L
S
100kHz, 20mV 350 444 540 μH
Leakage Inductance, L
L
100kHz, 250mV 6.28 8.00 μH
Interwinding Capacitance, C
WW
100kHz, 250mV 3.4 8.00 pF
Primary D.C. Resistance, R
DC
>0.1VDC 0.40 0.60
Ω
Volt-time Product, Et Pins 1/2 or 2/3 25 37 Vμs
All specifications typical at T
A
=25°C
