DSH 288/289（IEC 60065）半導(dǎo)體器件區(qū)分/音頻放大器故障條件

DSH 288

Subject: Semiconductor Devices

Question:

Does the wording "Semiconductor Devices" include:

a) integrated circuits

and

b) hybrid circuits consisting of discrete components mounted to a printed circuit board and encapsulated in a module ?

Decision:

Yes.

Both examples mentioned are considered to be "Semiconductor Devices " in the sense of the mentioned Clause.

問題：

“半導(dǎo)體器件”是否包括了：

a）集成電路和b）分立器件安裝在印制板上且封裝在模塊中的混合電路？

決定：

兩種電路都認(rèn)為屬于“半導(dǎo)體器件”范疇。

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DSH 289

Subject: Fault conditions on audio amplifiers

Question:

When applying fault conditions to an audio amplifier (scl. 4.3.9) to determine heating under fault conditions there are two possibilities to do this.

1. Adjusting the apparatus to deliver one-eighth of the non- clipped output power to the minimum rated load impedance [ 8 Ohms) and then changing the load to 4 Ohms without changing the adjustment.

2. Changing the load impedance to 4 Ohms, measuring the non-clipped output power into 4 Ohms, and then adjusting the output to one-eighth of the non-clipped output power.

Which possibility is to be used?

Decision:

Possibility 1 has to be used.

問題：

對音頻放大器施加單一故障時，可能有2種方法能確認(rèn)故障狀態(tài)下的發(fā)熱。

1、將1/8非削波輸出功率施加在最小額定阻抗（8Ω）上，然后再將阻抗換成4Ω，不做其他調(diào)整。

2、將阻抗換成4Ω，測量最大非削波輸出功率，再調(diào)整為1/8非削波輸出功率。

應(yīng)該用哪種方法？

決定：

方法1。

提示：

DSH 289決議時間有點(diǎn)早，可能很多朋友不清楚為什么是8Ω變成4Ω。由于喇叭阻抗規(guī)格基本是16Ω、8Ω、4Ω定值，如果額定阻抗是8Ω，故障試驗時要連接不利負(fù)載，即連接更小阻抗負(fù)載，因此可以選擇4Ω，當(dāng)然也可以選擇短路。

決議的重點(diǎn)是，先在額定阻抗上調(diào)整1/8非削波輸出功率，確認(rèn)放大器的工作狀態(tài)，然后再連接不利負(fù)載，才能保證試驗復(fù)現(xiàn)性。

關(guān)于1/8非削波相關(guān)內(nèi)容見以下鏈接：

音頻放大器測試時所用的音源信號

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