An integrated analog switch using a bidirectional transistor
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ABSTRACTS ON MICROELECTRONICS AND RELIABILITY
the design of digital counters suing micrologic integrated circuits. These criteria concern only th...
the design of digital counters suing micrologic integrated circuits. These criteria concern only the case in which the code is specified in advance. A "change function" is used, which allows specifying which input conditions are required to a memory element for it to change or remain in its present state, at the arrival of the next clock pulse. The integrated memory elements of the micrologic families are presented, both of the R T L and D T L type. Their logic properties are described and the input functions required for each memory element to follow a given code are derived. The general equations so obtained are used to derive the schematics of counters. A monolithic silicon class B h e a r i n g aid amplifier. M. J. HELLSTROM,SCP and Solid St. Technology, April (1966), p. 17. The use of a Class B output stage is essential in a hearing aid amplifier because low battery drain is a prime requirement. A balanced pre-amplifier design, while impractical using discrete components, forms a suitable driver for an integrated circuit class B output stage, d.c. and a.c. negative feedback are used for bias stabilization and volume control, respectively. The control of idling current by means of a tapped resistor is analyzed. Variation of gain with volume control resistance is calculated and compared with measured results. Typical performance is 3 mW output at 5 per cent total harmonic distortion and 4.1 mA battery current. Voltage gain is 72 dB and idling current 1"0 mA. Parameter distributions on production runs are given. An intzgratod mmlog ~ r i t c h using a bidirzetlonal . ~ ~ . . r , R. Y. HUNG, SCP and Solid St. Technology, July (1966), p. 15. An integrated analog switch Iabricated in a monolithic silicon block is described. The circuit functions are discussed and analysed. The device fabrication considerations are outlined and a summary of electrical parameters is presented. Proper tost-point allocation. H. J. J~LINVKand H. T. BREEN,Electro-Technology, June (1966), p. 50. As systems become more complex, the job of testing and maintaining them be.comes increasingly difficult. Some of the difficulty lies in the fact that outmoded test techniques are being used. The number and location of test points is an important factor in the efficiency with which testing can be conducted.