The ultra-small MAX870/MAX871 monolithic, CMOS charge-pump inverters accept input voltages ranging from +1.4V to +5.5V. The MAX870 operates at 125kHz, and the MAX871 operates at 500kHz. Their high efficiency (90%) and low operating current (0.7mA for the MAX870) make these devices ideal for both battery-powered and board-level voltage-conversion applications.
Oscillator control circuitry and four power MOSFET switches are included on-chip. A typical MAX870/ MAX871 application is generating a -5V supply from a +5V logic supply to power analog circuitry. Both parts come in a 5-pin SOT23-5 package and can deliver 25mA with a voltage drop of 500mV.
For a similar device with logic-controlled shutdown, refer to the MAX1720/MAX1721. For applications requiring more power, the MAX860 delivers up to 50mA with a voltage drop of 600mV, in a space-saving uMAX package.
Oscillator control circuitry and four power MOSFET switches are included on-chip. A typical MAX870/ MAX871 application is generating a -5V supply from a +5V logic supply to power analog circuitry. Both parts come in a 5-pin SOT23-5 package and can deliver 25mA with a voltage drop of 500mV.
For a similar device with logic-controlled shutdown, refer to the MAX1720/MAX1721. For applications requiring more power, the MAX860 delivers up to 50mA with a voltage drop of 600mV, in a space-saving uMAX package.
MAX870, MAX871 应用/使用
电池供电设备 | |
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蜂窝电话 |
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手持终端、PDA |
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从5V逻辑电源产生本地-5V电源 |
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医疗仪器 |
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小型LCD板 |
MAX870, MAX871应用电路
典型工作电路