782485 Series www.murata-ps.com ADM2485 Compatible Converter Transformers SELECTION GUIDE Nominal Input Nominal Max. Output Isolation Turns Package Output Voltage Current Voltage Voltage Order Code Ratio Style V V mA VRMS 782485/35C 3.3 6.0 200 2500 1CT:2.2CT DIL 782485/55C 5.0 6.0 200 2500 1CT:1.5CT DIL CHARACTERISTICS 782485/35C 782485/35C 782485/55C Parameter Conditions Units Typ. Max. Typ. Max. FEATURES Primary Inductance, L 100kHz, 10mV 234 513 H P RoHS compliant Leakage Inductance, L 100kHz, 10mV 168 192 nH L Interwinding Capacitance, C 100kHz, 10mV 24 50 37 50 pF WW Analog Devices ADM2485 compatible Primary DC Resistance, R <0.1VDC 273 500 383 600 m DC 1 2.5kVrms isolation Volt-time Product, Et 5kHz, 5V 12 19 Vs Industry-standard pinout ABSOLUTE MAXIMUM RATINGS UL 94 V-0 package materials Operating free air temperature range -40C to 85C Low pro le Storage temperature range -50C to 125C Isolation voltage ( ash tested for 1 second) 2.5kVrms Toroidal construction 2 SOLDERING INFORMATION Fully encapsulated Peak wave solder temperature 300C for 10 seconds Industrial temperature range Pin nish Matte tin Surface mount versions available soon Speci cations typical at T = 25C A 1 Where pulse applied across pins 1 and 2. Recommended by Analog Devices, Inc. 2 For further information, please visit www.murata-ps.com/rohs Backward compatible with Sn/Pb soldering systems TECHNICAL NOTES ISOLATION VOLTAGE REPEATED HIGH-VOLTAGE ISOLATION TESTING Hi Pot Test, Flash Tested, Withstand Voltage, Proof Volt- It is well known that repeated high-voltage isolation DESCRIPTION age, Dielectric Withstand Voltage & Isolation Test Voltage testing of a barrier component can actually degrade The 782485 series of converter transformers are are all terms that relate to the same thing, a test voltage, isolation capability, to a lesser or greater degree speci cally designed for use with Analog Devices applied for a speci ed time, across a component designed depending on materials, construction and environ- chipsets to provide isolated RS-485 and RS-422 to provide electrical isolation, to verify the integrity of that ment. This series has toroidal isolation transformers, isolation. with no additional insulation between primary and interfaces. Carefully controlled turns ratios secondary windings of enameled wire. While parts ensure consistent performance whilst a toroidal All products in this series are 100% production tested at can be expected to withstand several times the their stated isolation voltage. construction minimises EMI. stated test voltage, the isolation capability does de- A question commonly asked is, What is the continuous pend on the wire insulation. Any material, including voltage that can be applied across the part in normal opera- this enamel (typically polyurethane) is susceptible tion to eventual chemical degradation when subject to For a part holding no speci c agency approvals both input very high applied voltages thus implying that the and output should normally be maintained within SELV limits number of tests should be strictly limited. We there- i.e. less than 42.4V peak, or 60VDC. The isolation test volt- fore strongly advise against repeated high voltage age represents a measure of immunity to transient voltages isolation testing, but if it is absolutely required, that and the part should never be used as an element of a safety the voltage be reduced by 20% from speci ed test isolation system. The part could be expected to function cor- voltage. rectly with several hundred volts offset applied continuously This consideration equally applies to agency recog- across the isolation barrier but then the circuitry on both nized parts rated for better than functional isolation sides of the barrier must be regarded as operating at an where the wire enamel insulation is always supple- unsafe voltage and further isolation/insulation systems must mented by a further insulation system of physical form a barrier between these circuits and any user-acces- spacing or barriers. sible circuitry according to safety standard requirements. For full details go to www.murata-ps.com/rohs www.murata-ps.com/support KMP 782485C A04 Page 1 of 2782485 Series ADM2485 Compatible Converter Transformers PACKAGE SPECIFICATIONS MECHANICAL DIMENSIONS RECOMMENDED FOOTPRINT DETAILS 9.77 (0.385) Max. TOP VIEW 2.54 (0.10) Primary Secondary 1 6 2.54 (0.10) 9.14 2 5 (0.360) Max. 782485/35C 34 XYYWW +0.15 (0.006) 1.20 (0.05) -0.00 (0.000) 6.35 (0.25) 3.440.50 (0.1350.02) 0.30(0.012) 0.6 (0.024) 0.20(0.008) 10.160.40 2.54 (0.400.016) (0.1) Unless otherwise stated all dimensions in mm (inches) 0.25 (0.01). 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. Package Weight 1.0g TYP. All pins on a 2.54(0.1) pitch and within 0.25(0.01) of true position. TUBE OUTLINE DIMENSIONS 10.65 - 11.65 (0.419 - 0.459) Unless otherwise stated all dimensions in mm (inches) 4.00 (0.16) 0.25 (0.01). Tube length: 5002 (19.70.08) 0.600.15 12.95 Tube quantity: 50 (0.0240.006) (0.51) Tube material: Antistatic coated clear PVC. 5.20 (0.21) 3.80 (0.15) 15.70 (0.62) Murata Power Solutions, Inc. Murata Power Solutions, Inc. makes no representation that the use of its products in the circuits described herein, or the use of other 11 Cabot Boulevard, Mans eld, MA 02048-1151 U.S.A. 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. Speci cations are subject to change without ISO 9001 and 14001 REGISTERED notice. 2011 Murata Power Solutions, Inc. www.murata-ps.com/support KMP 782485C A04 Page 2 of 2