Portable, battery-powered operation of electronic apparatushas become increasingly desirable. Medical, remotedata acquisition, power monitoring and other applicationsare good candidates for battery operation. In some circumstances,due to space, power or reliability considerations,it is preferable to operate the circuitry from a single 1.5Vcell. Unfortunately, a 1.5V supply eliminates almost alllinear ICs as design candidates. In fact, the LM10 opamp-reference and the LT®1017/LT1018 comparators arethe only IC gain blocks fully specifi ed for 1.5V operation.Further complications are presented by the 600mV dropof silicon transistors and diodes. This limitation consumesa substantial portion of available supply range, makingcircuit design diffi cult. Additionally, any circuit designedfor 1.5V operation must function at end-of-life batteryvoltage, typically 1.3V. (See Box Section, “Componentsfor 1.5V Operation.”)
Portable, battery-powered operation of electronic apparatushas become increasingly desirable. Medical, remotedata acquisition, power monitoring and other applicationsare good candidates for batteryoperation. In some circumstances,due to space, power or reliability considerations,it is preferable to operate the circuitry from a single 1.5Vcell. Unfortunately, a 1.5V supply eliminates almost alllinear ICs as design candidates. In fact, the LM10 opamp-reference and the LT®1017/LT1018 comparators arethe only IC gain blocks fully specifi ed for 1.5V operation.Further complications are presented by the 600mV dropof silicon transistors and diodes. This limitation consumesa substantial portion of available supply range, makingcircuit design diffi cult. Additionally, any circuit designedfor 1.5V operation mustfunction at end-of-life batteryvoltage, typically 1.3V. (See Box Section, “Componentsfor 1.5V Operation.”)
In predominantly digital systems it is often necessaryto include linear circuit functions. Traditionally, separatepower supplies have been used to run the linear components(see Box, “Linear Power Supplies—Past, Present,and Future”).
飛機電網(wǎng)故障時，機載電氣盒必須在延遲時間內(nèi)切斷電網(wǎng)，保護機載設(shè)備。采用AT89S52設(shè)計的電氣盒測試儀能夠測試電氣盒保護功能，測量延遲時間。實際應(yīng)用結(jié)果表明，該測試儀具有測量準(zhǔn)確、可靠性高、成本低等優(yōu)點。
Abstract:
The helicopter-electrical-Box must shut off the helicopter power，protect the equipments of the helicopter when the helicopter power is failed.The tester for the helicopter-electrical-Box based on AT89S52is used for testing the protect-ing function and measuring the delay time.Application results show this tester has some advantages,such as accurate mea-surement,high dependability,economical cost etc.
