EPC9051 TDK

Demonstration System EPC9051 Quick Start Guide EPC2037 High Frequency Class-E Power AmplifierQUICK START GUIDE EPC9051 DESCRIPTION Table 1: Performance Summary (T = 25C) EPC9051 A The EPC9051 is a high efficiency, differential mode class-E amplifier Symbol Parameter Conditions Min Max Units Class-E Configuration 0 20 V development board that can operate up to 15 MHz. Higher frequency Main Supply Voltage Current Mode Class-D operation may be possible but is currently under evaluation. The purpose V 0 30 V IN Range Configuration of this development board is to simplify the evaluation process of class-E Push-Pull Configuration 0 40 V amplifier technology using eGaN FETs by allowing engineers to easily Control Supply Input V 7 12 V DD Range mount all the critical class-E components on a single board that can be Switch Node Output easily connected into an existing system. I 1* A OUT Current (each) This board may also be used for applications where a low side switch is Oscillator Input V Input Low -0.3 1.5 V OSC Threshold utilized. Examples include, and are not limited to, push-pull converters, Input High 3.5 5 V current-mode Class D amplifiers, common source bi-directional switch, * Maximum current depends on die temperature actual maximum current will be subject to switching and generic high voltage narrow pulse width applications such as LiDAR. frequency, bus voltage and thermals. The amplifier board features the 100 V rated EPC2037 eGaN FET. The amplifier is set to operate in differential mode and can be re-configured to operate in single-ended mode. The key feature of this development board is that it does not require a gate driver for the eGaN FETs and is driven directly from logic gates. A separate logic supply regulator has also been provided on the board. For more information on the EPC2037 eGaN FETs please refer to the datasheet available from EPC at www.epc-co.com. The datasheet should be read in conjunction with this quick start guide. DETAILED DESCRIPTION The Amplifier Board (EPC9051) Figure 1 shows the schematic of a single-ended, class-E amplifier with ideal operation waveforms where the amplifier is connected to a tuned load such as a highly resonant wireless power coil. The amplifier has not been configured due to the specific design requirements such EPC9051 amplifier board photo as load resistance and operating frequency. The design equations of the specific class-E amplifier support components are given in this guide Class-E amplifier operating limitations and specific values suitable for a RF amplifier application can then be The impact of load resistance variation is significant to the performance calculated. of the class-E amplifier, and must be carefully analyzed to select the Figure 2 shows the differential mode class-E amplifier EPC9051 demo board optimal design resistance. power circuit schematic. In this mode the output is connected between The impact of load resistance (R Real part of Z ) variation on the Out 1 and Out 2. A block-wave external oscillator with 50% duty cycle Load Load operation of the class-E amplifier is shown in figure 3. When operating and 0 V 5 V signal amplitude is used as a signal for the board. Duty cycle a class-E amplifier with a load resistance (R Real part of Z ) modulation is recommended only for advanced users who are familiar with Load Load that is below the design value (see the waveform on the left of the class-E amplifier operation and require additional efficiency. same load), the load tends to draw current from the amplifier too The EPC9051 is also provided with a 5 V regulator to supply power quickly. To compensate for this condition, the amplifier supply to the logic circuits on board. Adding a 0 resistor in position voltage is increased to yield the required output power. The shorter R90 allows the EPC9051 to be powered using a single-supply duration of the energy charge cycle leads to a significant increase in voltage however in this configuration the maximum operating voltage the voltage to which the switching device is exposed. This is done range is limited to between 7 V and 12 V. in order to capture sufficient energy and results in device body Single-ended Mode operation diode conduction during the remainder of the device off period. This period is characterized by a linear increase in device losses as a Although the default configuration is differential mode, the demo board function of decreasing load resistance (R ). Load can be re-configured for single-ended operation by shorting out C74 (which disables only the drive circuits) and connecting the When operating the class-E amplifier with a load resistance (R ) that is Load load between Out 1 and GND only (see figures 2 and 5 for details). above the design value (see the waveform on the right of figure 3), the PAGE 2 EPC EFFICIENT POWER CONVERSION CORPORATION WWW.EPC-CO.COM COPYRIGHT 2016