×

MAX1884, MAX1885 pdf datasheet

消耗积分:2 | 格式:rar | 大小:444 | 2009-01-11

分享资料个

The MAX1778/MAX1880–MAX1885 multiple-output DC-DC converters provide the regulated voltages required by active matrix thin-film transistor (TFT) liquid crystal displays (LCD) in a low-profile TSSOP package. One high-power step-up converter and two low-power charge pumps convert the 2.7V to 5.5V input voltage into three independent output voltages. A built-in linear regulator and VCOM buffer complete the power-supply requirements.

The main step-up converter accurately generates an externally set output voltage up to 13V that can supply the display's row/column drivers. The converter's high switching frequency and current-mode PWM architecture provide fast transient response and allow the use of small low-profile inductors and ceramic capacitors. The low-power BiCMOS control circuitry and internal 14V switch (0.35≈ N-channel MOSFET) enable efficiencies up to 91%.

The dual low-power charge pumps (MAX1778/ MAX1880/MAX1881/MAX1882 only) independently regulate one positive output (VPOS) and one negative output (VNEG). These low-power outputs use external diode and capacitor stages (as many stages as required) to regulate output voltages up to +40V and -40V. A unique control scheme minimizes output ripple as well as capacitor sizes for both charge pumps.

A resistor-programmable, 40mA, low-dropout linear regulator (MAX1778/MAX1881/MAX1883/MAX1884 only) provides preregulation or postregulation for any of the supplies. For higher current applications, an external transistor can be added. Additionally, the VCOM buffer provides a high current output that is ideal for driving the capacitive backplane of TFT LCD panels. The VCOM buffer's output voltage is preset with an internal 50% resistive-divider or can be externally adjusted for other voltages.

The MAX1778/MAX1880–MAX1885 are protected against output undervoltage and thermal overload conditions by a latched fault detection circuit that shuts down the device. All devices are available in the ultra-thin TSSOP package (1.1mm max height).

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

评论(0)
发评论

下载排行榜

全部0条评论

快来发表一下你的评论吧 !