The HD 66137T is a 240-channel common driver which drives a dot matrix STN LCD panel. By changing the mode, this can be applied to 240- and 200- and 160- channel output. Through the use of a 43-V highvoltage CMOS process technology, a high-voltage drive of +21.5 V and 21.5 V, centering on VM is possible. 21.5V generated from +21.5 V with built-in switching circuit and external capacity. Low logicdrive voltage (3 V) is used. This device is used together with the segment driver HD66130, HD66134ST or HD66136.