Abstract: A communication system (20) is provided with multiple purpose personal communication devices (50 and 150). Each communication device (50 and 150) includes a touch-sensitive visual display (60 and 160) to communicate text and graphic information to and from the user and for operating the communication device (50 and 150). Voice activation (78) and voice control capabilities (76) are included within communication devices (50 and 150) to perform the same functions as the touch-sensitive visual display (60 and 160). The communication device includes a built-in modem (82), audio input and output (52 and 53), telephone jacks (86), and wireless communication (90). A plurality of application modules (100) are used with personal communication devices (50 and 150) to perform a wide variety of communication functions such as information retrievable, on-line data base services, electronic and voice mail.

Abstract: A CHE programmed memory device (30) avoids forward biasing at an isolated P-well (38) junction with a deep N-well (36) and prevents emitting electrons that may cause voltage buildup across the isolated P-well region (38) by applying a forward bias current (50) or voltage source (40) connected to the deep N-well region (36) for slightly forward biasing the deep N-well region. This maintains the voltage drop of isolated P-well region (38) below the diode turn-on voltage.

Abstract: An adaptive transmission line termination which includes a variable voltage controlled resistor (16) connected either in series with the sending end of transmission line (10) or in parallel with the receiving end of line (10). The resistance of resistor (16) is varied in dependence upon the half voltage appearing on line (10) in order to match the characteristic impedance of line (10) for the series or source termination case. In the parallel termination case, the resistance of resistor (34) is varied in dependence upon the voltage appearing at the input of gate (14) to match the characteristic impedance of line (10).