■Precautions in Designing a Memory Backup Circuit

   備份存儲(chǔ)器電路設(shè)計(jì)注意事項(xiàng)

A primary lithium battery is not rechargeable.

When used for memory backup in combination with another power source, current may flow into the battery from the other source. To prevent this, include a protection diode and resistor in the circuit so that no battery charging or over discharging can occur.

Allowable Range of Diode Back-Leakage Current

To prevent the battery from being charged by the main power source, be sure to use a back-current prevention diode and a protection resistor. Select a silicon diode or a Schottky diode with minimum leakage current, and design the circuit so that the amount of charging due to leakage current does not exceed 1% of the nominal battery capacity over the total period of use.   （鋰電池組不可充電。)

(當(dāng)使用于備份存儲(chǔ)器時(shí)與其它電源聯(lián)合，電流可能會(huì)從其它電源流入電池。為阻止其發(fā)生，在電路中加入保護(hù)二極管和電阻器，那么電池充電和過放電將可避免。

返回的泄露電流在二極管允許范圍內(nèi)。

為阻止電池被主電源充電，務(wù)必使用逆流保護(hù)二極管和保護(hù)電阻器。選擇低值泄露電流的硅二極管或肖特基二極管，設(shè)計(jì)電路以致電池使用全程中由于泄露電流損失的量不超過電池標(biāo)準(zhǔn)容量的1%）