AD7575

The AD7575 is a high speed 8-bit ADC with a built-in track/hold function. The successive approximation conversion technique is used to achieve a fast conversion time of 5 µs, while the built-in track/hold allows full-scale signals up to 50 kHz (386 µV/ms slew rate) to be digitized. The AD7575 requires only a single +5 V supply and a low cost, 1.23 V bandgap reference in order to convert an input signal range of 0 to 2 V_REF.

The AD7575 is designed for easy interfacing to all popular 8-bit microprocessors using standard microprocessor control signals (CS and RD) to control starting of the conversion and reading of the data. The interface logic allows the AD7575 to be easily configured as a memory mapped device, and the part can be interfaced as SLOW-MEMORY or ROM. All data outputs of the AD7575 are latched and three-state buffered to allow direct connection to a microprocessor data bus or I/O port.

The AD7575 is fabricated in an advanced, all ion-implanted high speed Linear Compatible CMOS (LC²MOS) process and is available in a small, 0.3" wide, 18-pin DIP or in 20-terminal surface mount packages.

PRODUCT HIGHLIGHTS

1. Fast Conversion Time/Low Power
   The fast, 5 µs, conversion time of the AD7575 makes it suitable for digitizing wideband signals at audio and ultrasonic frequencies while retaining the advantage of low CMOS power consumption.
2. On-Chip Track/Hold
   The on-chip track/hold function is completely self-contained and requires no external hold capacitor. Signals with slew rates up to 386 mV/µs (e.g., 2.46 V peak-to-peak 50 kHz sine waves) can be digitized with full accuracy.
3. Low Total Unadjusted Error
   The zero, full-scale and linearity errors of the AD7575 are so low that the total unadjusted error at any point on the transfer function is less than 1 LSB, and offset and gain adjustments are not required.
4. Single Supply Operation
   Operation from a single +5 V supply with a low cost +1.23 V bandgap reference allows the AD7575 to be used in 5 V microprocessor systems without any additional power supplies.
5. Fast Digital Interface
   Fast interface timing allows the AD7575 to interface easily to the fast versions of most popular microprocessors such as the Z80H, 8085A-2, 6502B, 68B09 and the DSP processor, the TMS32010.