By using a half-flash conversion technique, the 8-bit ADC0820 CMOS A/D offers a 1.5µs conversion time while dissipating a maximum 75mW of power. The half-flash technique consists of 31 comparators, a most significant 4-bit ADC and a least significant 4-bit ADC.
The input to the ADC0820 is tracked and held by the input sampling circuitry, eliminating the need for an external sample-and-hold for signals slewing at less than 100mV/µs.
For ease of interface to microprocessors, the ADC0820 has been designed to appear as a memory location or I/O port without the need for external interfacing logic.
• Built-in track-and-hold function
• No missing codes
• No external clocking
• Single supply—5VDC
• Easy interface to all microprocessors, or operates stand-alone
• Latched 3-State outputs
• Logic inputs and outputs meet both MOS and TTL voltage level
• Operates ratiometrically or with any reference value equal to or
less than VDD
• 0V to 5V analog input voltage range with single 5V supply
• No zero- or full-scale adjust required
• Overflow output available for cascading
• 0.3″ standard width 20-pin DIP
• Microprocessor-based monitoring and control systems
• Transducer/µP interface
• Process control
• Logic analyzers
• Test and measurement