76250ENC, 76253/XXENC www.murata-ps.com EN Approved MAX250/251/253 Compatible Converter Transformers SELECTION GUIDE Order Code Input Voltage V Output Voltage V Max. Output Current mA Isolation Voltage VDC Turns Ratio 1CT:1 76250ENC - - - 6000 76253/35ENC 3.3 5.0 100 6000 1:√5 76253/55ENC 5.0 5.0 200 6000 1:1.33 76250ENC CHARACTERISTICS FEATURES RoHS compliant Maxim MAX250/MAX251/MAX253 compatible BS EN 60950 approved Isolation to 6kVDC Toroidal construction Parameter Conditions Min. Typ. Max. Units Primary Inductance, LP (1&5) 10kHz, 100mV 1.0 2.0 2.5 mH Leakage Inductance, LL (1&5) 2 100kHz, 100mV 35 40 μH Interwinding Capacitance, CWW (1&2) 100kHz, 100mV 1.5 3.0 pF D.C. Resistance, RDC (1&5) <0.1VDC 1.0 2.0 Volt-time Product, ET (1&5) Vμs 76253/35ENC CHARACTERISTICS Parameter Conditions Min. Typ. 100kHz, 250mV 140 200 UL 94 V-0 package materials Primary Inductance, LP (1&5) Secondary Inductance, LS (2&6) 100kHz, 250mV 700 1000 Fully encapsulated Leakage Inductance, LL (1&5)2 100kHz, 250mV Interwinding Capacitance, CWW (1&2) 100kHz, 250mV D.C. Resistance, RDC (1&5) <0.1VDC Industry-standard pinout Compatible with RoHS soldering systems Backward compatible with Sn/Pb soldering systems Ω 50 Volt-time Product, ET (1&5) 5.0 Max. Units μH μH 7.0 μH 2.7 3.5 pF 0.4 0.8 25 35 Min. Typ. Ω Vμs 76253/55ENC CHARACTERISTICS DESCRIPTION The 76250ENC converter transformer is specifically designed for use with Maxim chipsets to provide isolated RS232 interfaces. A carefully controlled turns ratio ensures consistent performance whilst a toroidal construction minimises EMI. The 76253/XXENC converter transformers are specifically designed for use with the MAX253 chip set to provide isolated power supplies. The 5V version can supply 1W and the 3.3V version can supply 500mW. A centre tapped secondary winding allows for full bridge, half bridge or voltage doubling. The devices are fully approved to BS EN 60950 for use in telecoms applications. Parameter Conditions Max. Units Primary Inductance, LP (1&5) 100kHz, 250mV 80 150 μH Secondary Inductance, LS (2&6) 100kHz, 250mV 142 267 μH Leakage Inductance, LL (1&5)2 100kHz, 250mV 7.0 10.0 μH Interwinding Capacitance, CWW (1&2) 100kHz, 250mV 2.7 3.5 pF D.C. Resistance, RDC (1&5) <0.1VDC 0.5 0.9 Volt-time Product, ET (1&5) 30 40 Ω Vμs ABSOLUTE MAXIMUM RATINGS Operating free air temperature range 76250EN 0°C to 70°C Operating free air temperature range 76253/XXEN -40°C to 85°C Storage temperature range -50°C to 125°C Lead temperature 1.5mm from case for 10 seconds 300°C Peak current, IPK 76250EN 300mA Peak current, IPK 76253/XXEN 400mA Isolation voltage (flash tested for 1 second) 6000VDC SOLDERING INFORMATION3 For full details go to www.murata-ps.com/rohs Peak wave solder temperature 300˚C for 10 seconds Pin finish Matte tin All specifications typical at TA=25°C 1 Refer to mechanical dimensions for pin locations shown in brackets. 2 With pins 2 & 6 short circuited. 3 For further information, please visit www.murata-ps.com/rohs www.murata-ps.com/support KMP_7625XENC_B04 Page 1 of 4 76250ENC, 76253/XXENC EN Approved MAX250/251/253 Compatible Converter Transformers TYPICAL CHARACTERISTICS (VOLTAGE CURVES) VOLTAGE CURVES 76253/35ENC 10 8 Output Voltage (V) Output Voltage (V) 8 6 4 6 4 2 0 76253/55ENC 10 2 0 20 40 60 80 0 100 0 Output Current (mA) 100 200 300 Output Current (mA) 400 EFFICIENCY CURVES 76253/35ENC 80 80 60 60 40 40 20 20 0 76253/55ENC 100 Efficiency (%) Efficiency (%) 100 0 20 40 60 80 0 100 0 100 Output Current (mA) 200 300 400 Output Current (mA) VOLTAGE DEVIATION 76253/35ENC 105 100 95 90 -50 -25 0 25 76253/55ENC 110 Voltage deviation from nominal 25ºC output (%) Voltage deviation from nominal 25ºC output (%) 110 50 Temperature (ºC) 75 100 105 100 95 90 -50 -25 0 25 50 75 100 Temperature (ºC) All curves are derived from testing with the Maxim MAX235 IC using the circuit shown in application note MPAN-03 (download at http://www.murata-ps.com/data/apnotes/mpan-03.pdf). www.murata-ps.com/support KMP_7625XENC_B04 Page 2 of 4 76250ENC, 76253/XXENC EN Approved MAX250/251/253 Compatible Converter Transformers PACKAGE SPECIFICATIONS MECHANICAL DIMENSIONS 15.00 (0.59) 2 1 15.00 (0.59) 76250ENC XYYWW 3 5 12.00 (0.472) 12.50 (0.492) 2.54 (0.1) 4* 7.50 (0.295) 6 4.10 (0.161) Ø0.56±0.05 (Ø0.022±0.002) Pin Connections 76250EN (Top View) Primary 1 Secondary 2 6 1 Primary Secondary 2 3 4 5 6 TUBE DIMENSIONS * 76250EN Pin not fitted. Unless otherwise stated all dimensions in mm (inches) ±0.25mm (±0.01). All pins on a 2.54mm (0.1") pitch and within ±0.25mm (0.01") of true position. RECOMMENDED FOOTPRINT DETAILS 2.54 (0.100) 3 2.54 (0.100) 2.42 (0.095) Pin Connections 76253/XXEN (Top View) 3 5 10.16 (0.4) Tube length: 480±2.00mm (18.90±0.079"). Tube quantity: 30 Tube material: Antistatic coated clear pvc. Unless otherwise stated all dimensions in mm (inches) -0.00 +0.50 (-0.00 +0.020). x6 HOLES* Ø1.00+0.15-0.00 (Ø0.039+0.006-0.000) Holes may be omitted for variants with fewer than 6 pins. Unless otherwise stated all dimensions in mm (inches) ±0.25 (0.01). All pins on a 2.54 (0.1) pitch and within ±0.25 (0.01) of true position. www.murata-ps.com/support KMP_7625XENC_B04 Page 3 of 4 76250ENC, 76253/XXENC EN Approved MAX250/251/253 Compatible Converter Transformers TECHNICAL NOTES ISOLATION VOLTAGE REPEATED HIGH-VOLTAGE ISOLATION TESTING ‘Hi Pot Test’, ‘Flash Tested’, ‘Withstand Voltage’, ‘Proof Voltage’, ‘Dielectric Withstand Voltage’ & ‘Isolation Test Voltage’ are all terms that relate to the same thing, a test voltage, applied for a specified time, across a component designed to provide electrical isolation, to verify the integrity of that isolation. It is well known that repeated high-voltage isolation testing of a barrier component can actually degrade isolation capability, to a lesser or greater degree depending on materials, construction and environment. We therefore strongly advise against repeated high voltage isolation testing, but if it is absolutely required, that the voltage be reduced by 20% from the specified test voltage. All products in this series are 100% production tested at their stated isolation voltage. This series is recognised by the British Standards Institution to a working voltage of 300Vrms for Reinforced Insulation systems. Murata Power Solutions, Inc. 11 Cabot Boulevard, Mansfield, MA 02048-1151 U.S.A. ISO 9001 and 14001 REGISTERED Murata Power Solutions, Inc. makes no representation that the use of its products in the circuits described herein, or the use of other technical information contained herein, will not infringe upon existing or future patent rights. The descriptions contained herein do not imply the granting of licenses to make, use, or sell equipment constructed in accordance therewith. Specifications are subject to change without notice. © 2011 Murata Power Solutions, Inc. www.murata-ps.com/support KMP_7625XENC_B04 Page 4 of 4