Leakage Compensated Reference Voltage Generator
Original Publication Date: 1980-Jan-01
Included in the Prior Art Database: 2005-Feb-13
The reference voltage is typically generated from a 4K loop by writing half charge in the reference loop, as shown in Fig. 1. This approach gives a better margin for temperature and low frequency operation of the device because the reference loop collects the same charge due to leakage as the other loops collect. One of the problems in smaller cell design and interlaced structure is that the charge is trapped in the serial register during the transfer from serial to parallel. This effect causes the reference voltage not to be in the midway of the voltage required to sense a "one" and "zero". To demonstrate this let us assume the following: Q = charge written in all loops (Delta)Q = charge trapped in serial register Q(R) = Q/2 charge written in reference loop.