This post explains for the converter.
The Part Number is ADC-0803.
The function of this semiconductor is A/D Converter.
Preview images :
The ADC-0803 family are CMOS 8-Bit, successive-approxi-mation A/D converters which use a modified potentiometric ladder and are designed to operate with the 8080A control bus via three-state outputs. These converters appear to the processor as memory locations or I/O ports, and hence no interfacing logic is required.
The differential analog voltage input has good common-mode-rejection and permits offsetting the analog zero-input-voltage value. In addition, the voltage reference input can be adjusted to allow encoding any smaller analog voltage span to the full 8 bits of resolution. […]
• Conversion Time < 100µs
• Easy Interface to Most Microprocessors
• Will Operate in a “Stand Alone” Mode
• Differential Analog Voltage Inputs
• Works with Bandgap Voltage References
• TTL Compatible Inputs and Outputs
Other data sheets are available within the file:
ADC0803LCN, ADC0803LCD, ADC0803LCWM, ADC0803LD