Microwave Magnetrons Being Replaced by Solid State
22nd October 2014
The product of interest is Freescale’s new MHT1003N, a 250 watt LDMOS transistor for 2.45 GHz that provides a power-added efficiency (PAE) of 58%. Another device targeting RF heating applications is the MHT1002N for 915 MHz that can deliver 350 watts at 63% PAE. Using the MHT1003N, manufacturers can use from one to eight of these 250 W units to build a microwave oven with the desired power level. And the magnetron’s 4 kV power supply goes away in place of a supply of 28 to 50 volts. Furthermore, the crude on-off control of the magnetron can be replaced with full variable power control. Using multiple antennas, one per amplifier, provides better coverage of the cooking chamber. This allows food to be cooked more precisely while the unit operates more efficiently. And the product lifetime is significantly greater.