The ADM660/ADM8660 is a charge-pump voltage converter that can be used to either invert the input supply voltage giving VOUT = –VIN or double it (ADM660 only) giving VOUT = 2 : VIN. Input voltages ranging from +1.5 V to +7 V can be inverted into a negative –1.5 V to –7 V output supply. This inverting scheme is ideal for generating a negative rail in single power supply systems. Only two small external capacitors are needed for the charge pump. Output currents up to 50 mA with greater than 90% efficiency are achievable, while 100 mA achieves greater than 80% efficiency. A Frequency Control (FC) input pin is used to select either 25 kHz or 120 kHz charge-pump operation. This is used to optimize capacitor size and quiescent current. With 25 kHz selected, a 10 µF external capacitor is suitable, while with 120 kHz the capacitor may be reduced to 2.2 µF. The oscillator frequency on the ADM660 can also be controlled with an external capacitor connected to the OSC input or by driving this input with an external clock. In applications where a higher supply voltage is desired it is possible to use the ADM660 to double the input voltage. With input voltages from 2.5 V to 7 V, output voltages from 5 V to 14 V are achievable with up to 100 mA output current. The ADM8660 features a low power shutdown (SD) pin instead of the external oscillator (OSC) pin. This can be used to disable the device and reduce the quiescent current to 300 nA.
声明:本文内容及配图由入驻作者撰写或者入驻合作网站授权转载。文章观点仅代表作者本人,不代表电子发烧友网立场。文章及其配图仅供工程师学习之用,如有内容侵权或者其他违规问题,请联系本站处理。 举报投诉
全部0条评论
快来发表一下你的评论吧 !