78250 Series MAX250 Compatible Converter Transformers CHARACTERISTICS 78250C/78250MC Parameter Conditions Min. Typ. Max. Units Primary Inductance, LP Leakage Inductance, LL Interwinding Capacitance, CWW Primary D.C. Resistance, RDC Volt-time Product, Et 10kHz, 100mV 100kHz, 100mV 100kHz, 100mV <0.1VDC Pins1/2 or 2/3 1.0 2.0 2.0 69 1.0 2.5 3.0 90 2.0 mH μH pF Ω 50 Vμs FEATURES CHARACTERISTICS 78250VC/78250MVC RoHS compliant Parameter Conditions Min. Typ. Max. Units Primary Inductance, LP Leakage Inductance, LL Interwinding Capacitance, CWW Primary D.C. Resistance, RDC Volt-time Product, Et 10kHz, 100mV 100kHz, 100mV 100kHz, 100mV <0.1VDC Pins1/2 or 2/3 1.0 2.0 35 9 1.4 2.5 40 12 1.8 mH μH pF Maxim MAX250 compatible Isolation to 4kVrms Industry-standard pinout Ω 50 Vμs Surface mount option UL 94 V-0 package materials Low profile Toroidal construction Fully encapsulated Industrial temperature range DESCRIPTION The 78250 series of converter transformers are specifically designed for use with Maxim chipsets to provide isolated RS232 interfaces. Carefully controlled turns ratios ensure consistent performance whilst a toroidal construction minimises EMI. ORDER CODE DETAILS Order Code 78250C / 78250VC 78250MC / 78250MVC 78250MC-R / 78250MVC-R Package Type 6 Pin DIL 6 Pin SM 6 Pin SM Operating free air temperature range Storage temperature range Lead temperature 1.5mm from case for 10 seconds Peak current, IPK Isolation voltage 78250(M)C (flash tested for 1 second) Isolation voltage 78250V(M)C (flash tested for 1 second) www.murata-ps.com -40°C to 85°C -50°C to 125°C 300°C 300mA 1.5kVrms 4.0kVrms All specifications typical at TA=25°C 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. This series has toroidal isolation transformers, with no additional insulation between primary and secondary windings of enameled wire. While parts can be expected to withstand several times the stated test voltage, the isolation capability does depend on the wire insulation. Any material, including this enamel (typically polyurethane) is susceptible to eventual chemical degradation when subject to very high applied voltages thus implying that the number of tests should be strictly limited. We therefore strongly advise against repeated high voltage isolation testing, but if it is absolutely required, that the voltage be reduced by 20% from specified test voltage. A question commonly asked is, “What is the continuous voltage that can be applied across the part in normal operation?” For full details go to www.murata-ps.com/rohs Quantity 50 50 500 ABSOLUTE MAXIMUM RATINGS All products in this series are 100% production tested at their stated isolation voltage. Packaging Type Tube Tube Tape & Reel For a part holding no specific agency approvals both input and output should normally be maintained within SELV limits i.e. less than 42.4V peak, or 60VDC. The isolation test voltage represents a measure of immunity to transient voltages and the part should never be used as an element of a safety isolation system. The part could be expected to function correctly with several hundred volts offset applied continuously across the isolation barrier; but then the circuitry on both sides of the barrier must be regarded as operating at an unsafe voltage and further isolation/insulation systems must form a barrier between these circuits and any user-accessible circuitry according to safety standard requirements. This consideration equally applies to agency recognized parts rated for better than functional isolation where the wire enamel insulation is always supplemented by a further insulation system of physical spacing or barriers. Technical enquiries - email: [email protected], tel: +44 (0)1908 615232 KMP_78250C_C02 Page 1 of 3 78250 Series MAX250 Compatible Converter Transformers PACKAGE SPECIFICATIONS MECHANICAL DIMENSIONS 6 Pin SM 6 Pin DIL 0.5 (12.70) 0.375 (9.52) Max. 0.375 (9.52) MAX 1 0.354 (9.0) Max. 78250C XYYWW Primary Secondary 6 1 0.354 (9.0) Max. 2 3 4 78250MC XYYWW 0.25 (6.35) Primary Secondary 6 2 5* 3 4 0.25 (6.35) 0.012±0.30 (0.008±0.20) 0.135±0.02 (3.44±0.50) 0.012(0.30) 0.008(0.20) 0.40 (10.16) 0.1 (2.54) 0.025 (0.63) 0.021 (0.53) 0.1 (2.54) 0.025 (0.63) 0.021 (0.53) 0.035 (0.90) Unless otherwise stated all dimensions in inches (mm) ±0.01 (0.25). All pins on a 0.1 (2.54) pitch and within ±0.01 (0.25) of true position. * Pin 5 is connected to secondary center tap. Package Weight 1.0g TYP. RECOMMENDED FOOTPRINT DETAILS 6 Pin DIL 6 Pin SM 0.10 (2.54) 0.06 (1.60) 0.10 (2.54) 0.10 (2.54) Ø0.05 (1.20) +0.006 (0.15) -0.000 (0.00) 0.04 (1.00) 0.45 (11.50) Unless otherwise stated all dimensions in inches (mm) ±0.01 (0.25). All pins on a 0.1 (2.54) pitch and within ±0.01 (0.25) of true position. TUBE OUTLINE DIMENSIONS SOLDERING INFORMATION1 0.43 (10.95) Unless otherwise stated all dimensions in inches (mm) ±0.01 (0.25). 0.16 (4.00) 0.023±0.005 (0.60±0.15) 0.51 (12.95) Tube length: 18.3±0.08 (465±2). Pin finish Pure tin dip Peak wave solder temperature 300˚C for 10 seconds Peak reflow temperature 220˚C 1 For further information, please visit www.murata-ps.com/rohs Tube material: Antistatic coated clear pvc. 0.22 (5.50) 0.15 (3.80) 0.62 (15.70) www.murata-ps.com Technical enquiries - email: [email protected], tel: +44 (0)1908 615232 KMP_78250C_C02 Page 2 of 3 78250 Series MAX250 Compatible Converter Transformers TAPE & REEL SPECIFICATIONS REEL OUTLINE DIMENSIONS 2.36 (60) Min. Ø15.039 (382) Max. 0.94-1.08 (23.9-27.4)* Ø 0.53 (13.50) 0.50 (12.80) Leader section 15.7 (400) Min. 3.9 (100) Min. 0.059 (1.50) Min. 1.20 (30.4) Max. Goods enclosure section 0.96 (24.4) 1.04 (26.4) Trailer section 6.3 (160) Min. Unless otherwise stated all dimensions in inches (mm) ±0.01(0.25). Ø 0.80 (20.20) Min. * Includes flange distortion at outer edge. Measured at hub. TAPE OUTLINE DIMENSIONS 0.453 (11.50) 0.157 (4.00) XYYWW Cover tape +0.004 +0.10 0.059 -0.000 (1.50 -0.00 ) 0.079 (2.00) 78250C 0.945 +0.012 (24.00 +0.30 -0.10 ) -0.004 0.069 (1.75) 0.369 (9.37) 0.472 (12.00) 0.024 (0.60) Max. Direction of unreeling 0.283 (7.20) Unless otherwise stated all dimensions in inches (mm) ±0.01(0.25). USA: Mansfield (MA), Tel: (800) 233 2765, email: [email protected] Canada: Toronto, Tel: (866) 740 1232, email: [email protected] Murata Power Solutions, Inc. 11 Cabot Boulevard, Mansfield, MA 02048-1151 U.S.A. Tel: (508) 339-3000 (800) 233-2765 Fax: (508) 339-6356 www.murata-ps.com email: [email protected] ISO 9001 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. © 2008 Murata Power Solutions, Inc. www.murata-ps.com UK: Milton Keynes, Tel: +44 (0)1908 615232, email: [email protected] France: Montigny Le Bretonneux, Tel: +33 (0)1 34 60 01 01, email: [email protected] Germany: München, Tel: +49 (0)89-544334-0, email: [email protected] Japan: Tokyo, Tel: 3-3779-1031, email: [email protected] Osaka, Tel: 6-6354-2025, email: [email protected] Website: www.murata-ps.jp China: Shanghai, Tel: +86 215 027 3678, email: [email protected] Guangzhou, Tel: +86 208 221 8066, email: [email protected] Technical enquiries - email: [email protected], tel: +44 (0)1908 615232 KMP_78250C_C02 Page 3 of 3