EPC 9104 Краткое руководство по эксплуатации - Страница 9

Просмотреть онлайн или скачать pdf Краткое руководство по эксплуатации для Материнская плата EPC 9104. EPC 9104 12 страниц. 15 w, 6.78 mhz class d wireless power system using the epc2014 egan fet

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THERMAL CONSIDERATIONS

The EPC9104 demonstration system showcases the EPC2014 eGaN

FET in a wireless application. Although the electrical performance

surpasses that for traditional Si devices, their relatively smaller

size does magnify the thermal management requirements. The

EPC9104 is intended for bench evaluation with low ambient tem-

perature and convection cooling with load power up to 10 W (the

heat-sink MUST be mounted to the board). The addition of forced

air cooling can signi cantly increase the power output of this sys-

tem, but care must be taken to not exceed the absolute maximum

die temperature of 125°C.

NOTE. The EPC9104 demonstration system does not have any current or thermal

protection on board. The source coil matching inductor will also dissipate signi -

cant power at load power > 10 W and care must be taken to force air cool this induc-

tor too during operation.

GENERAL PRECAUTIONS

• Do not operate the board without a heat-sink as the FETs will overheat and fail.

• Avoid contact with the coil feedback voltage as it can be as high as 300 Vpeak.

• Do not operate the system below resonance as the load will appear capaci-

tive and the losses in the FETs will become very high and lead to thermal

failure. When testing the system at various frequencies, always start higher

than 6.78 MHz and slowly reduce the frequency, whilst monitoring the source

coil current, until the desired setting or the peak amplitude has been reached

(resonant point). Operating below this frequency is considered below resonance.

• Do not operate the system on a solid metal (or conductive) surface without

the stando s provided as this will shunt the magnetic eld and lead to over-

current of the FETs.

• Do not apply magnetic materials to the coil magnetic elds as this will shift the

resonant operating points and can lead to failure.

Mechanically

Attached

Source Coil

to these

locations

Figure 5: Proper Connection and Measurement Setup for the Device Coil

Device Coil

Output

Voltage

(see Notes

for details)

Device Coil

Connection

EPC

EFFICIENT POWER CONVERSION

Figure 6: Proper Connection and Measurement Setup for the Device Board

Device

Board

Connection

Load

Current

(see Notes

for details)

*ONLY to be

used with

Shunt

removed

External

Load

(see Notes

for details)