UM9995

UM9995 ULTRA LOW MAGNETIC MRI SWITCHING DIODES DESCRIPTION KEY FEATURES The UM9995 was developed for switching applications in MRI systems that require an ultra low magnetic image. The UM9995 is also excellent for shunt mount applications with good switch performance from VHF and higher. The selection of the proper materials for the package insures the minimum magnetic image required for MRI applications. The performance is achieved using discrete low inductance PIN diodes assembled with special hardware to permit good electrical and mechanical properties The Microsemi UM9995 PIN diode is constructed using a fused-in-glass process, which results in a highly reliable, hermetic package. The process utilizes symmetrical, full faced metallurgical bonds to both surfaces of the silicon chip. This construction greatly minimizes the normal parasite inductance and capacitance found in conventional glass or ceramic packaged diodes, which employ straps, springs, or washers. Ultra low magnetic construction Low inductance package High power handling capability Low bias current requirement Excellent distortion properties Passivated chip Metallurgical bond Non-cavity design Thermally matching configuration Available in surface or shunt mount packages W WW . Microsemi . C OM This is an actual Magnetic Image of the standard UM9601 and the specially constructed UM9995 PIN diode (in a 3T MRI system). UM9995 UM9995 Fig. 1 Image of the UM9995 compared to standard Switch diode Copyright  2004 Rev. 0, 2004-10-15 Microsemi Page 1 UM9995 ULTRA LOW MAGNETIC MRI SWITCHING DIODES ELECTRICAL PARAMETERS @ 25°C (unless otherwise specified) Parameter Symbol Conditions Min Typ. Max Units W WW . Microsemi . C OM Series Resistance Total Capacitance Parallel Resistance Forward Voltage (Note 1) Carrier Lifetime I-Region Width Rs Ct Rp Vf I = 100 mA F = 100 MHz V = 100V F = 1MHz V = 100 V F = 100 MHz IF = 100 mA , If = 10 mA 100 2.0 80 0.4 0.85 0.6 1.2 - Ω pF kΩ V µs µm τ W Note: 1 Short duration test pulse used to minimize self – heating effect. ELECTRICAL PARAMETERS @25ºC (unless otherwise specified) Ρo Flange at 25ºC Free Air Peak Power (1 µs @ 25ºC) Storage Temperature Operating Temperature 7.5 W θt 20ºC/W 1.5 W 10 kW -65 to +150ºC -65 to +150ºC UM9995 UM9995 Copyright  2004 Rev. 0, 2004-10-15 Microsemi Page 2 UM9995 ULTRA LOW MAGNETIC MRI SWITCHING DIODES STYLE “G” W WW . Microsemi . C OM STYLE “SM” UM9995 UM9995 PRODUCT PRELIMINARY DATA – Information contained in this document is pre-production data, and is proprietary to Microsemi Corp. It may not be modified in any way without the express written consent of Microsemi Corp. Product referred to herein is not guaranteed to achieve preliminary or production status and product specifications, configurations, and availability may change at any time. Copyright  2004 Rev. 0, 2004-10-15 Microsemi Page 3