UMX1089 Datasheet | Microsemi

DESCRIPTION The UMX1089 diode series was designed to protect MRI receivers from high RF energy fields including long RF pulses and RF spike pulses present in most MRI machines. The UMX1089 acts as a passive protector (limiter) for the MRI receiver. No forward bias voltage is required to turn on the diode. It is self-biased by the RF transmitter pulse power. A switch driver is not needed for this receiver protection application. The UMX1089 process has been optimized for lower loss performance. Receiver protector diodes appear directly across the input port of the receiver. They are connected in antiparallel pairs to limit the RF carrier excursion in both polarities. They must, therefore, exhibit extremely low insertion loss, both in the “on” state (high power present) and the “off” state (receiver power present) so as not to decrease the receiver’s sensitivity. The UMX1089 diodes are available in two package configurations for flexibility in design. KEY FEATURES - Available in surface mount package. - Metallurgical bond - Passivated chip - Low magnetic construction - Non cavity design - Optimized for low loss performance - Low capacitance at 0V bias - Low conductance at 0V bias - patible with automatic insertion equipment - Ro HS pliant 1 Note 1: Ro HS pliant versions are supplied with a matte Tin finish or Silver finish. Ro HS part numbers are: UMX1089B - matte Tin finish UMX1089SM - Silver finish Pb/Sn terminal plating available. Consult factory for details. APPLICATION/BENEFITS - MRI Receiver Protection - Body Coil Isolation ABSOLUTE MAXIMUM RATINGS @ 25C Rating Peak Repetitive Reverse Voltage Working Peak Reverse Voltage DC Blocking Voltage RMS Reverse Voltage Non-Repetitive Peak Forward Surge Current 8.3ms Single half sine wave Storage Temperature Operating Temperature Symbol VRRM VRWM VR V R (RMS) IFSM TSTG TOP Value 50 2.5 -65 to +150 -65 to +150 Unit V A ºC ºC For the most current data, consult MICROSEMI’s website: .MICROSEMI. Specifications are...