Analog Devices

The AD7818 andAD7817are 10-bit, single- and 4-channel A/D converters with on-chip temperature sensor that can operate from a single 2.7 V to 5.5 V power supply. Each part contains a 9 μs successive-approximation converter based around a capacitor DAC, an on-chip temperature sensor with an accuracy of ±2°C, an on-chip clock oscillator, inherent track-and-hold functionality and an on-chip reference (2.5 V). The AD7816 is a temperature monitoring only device in a SOIC/MSOP package.The on-chip temperature sensor of the AD7817 and AD7818 can be accessed via Channel 0. When Channel 0 is selected and a conversion is initiated, the resulting ADC code at the end of the conversion gives a measurement of the ambient temperature with a resolution of ±0.25°C. See Temperature Measurement section of this data sheet.The AD7816, AD7817, and AD7818 have a flexible serial interface that allows easy interfacing to most microcontrollers. The interface is compatible with the Intel 8051, Motorola SPI®and QSPI™protocols and National Semiconductors MICROWIRE™protocol. For more information refer to the Serial Interface section of this data sheet.The AD7817 is available in a narrow body 0.15" 16-lead small outline IC (SOIC), in a 16-lead, thin shrink small outline package (TSSOP), while the AD7816/AD7818 come in an 8-lead small outline IC (SOIC) and an 8-lead microsmall outline IC (MSOP).

The AD7819 is a high speed, microprocessor-compatible, 8-bit analog-to-digital converter with a maximum throughput of 200 kSPS. The converter operates off a single +2.7 V to +5.5 V supply and contains a 4.5 µs successive approximation A/D converter, track/hold circuitry, on-chip clock oscillator and 8-bit wide parallel interface. The parallel interface is designed to allow easy interfacing to microprocessors and DSPs. Using only address decoding logic the AD7819 is easily mapped into the microprocessor address space.When used in its power-down mode, the AD7819 automatically powers down at the end of a conversion and powers up at the start of a new conversion. This feature significantly reduces the power consumption of the part at lower throughput rates. The AD7819 can also operate in a high speed mode where the part is not powered down between conversions. In this mode of operation the part is capable of providing 200 kSPS throughput.The part is available in a small, 16-pin 0.3" wide, plastic dual-in-line package (DIP); in a 16-pin, 0.15" wide, narrow body small outline IC (SOIC) and in a 16-pin, narrow body, thin shrink small outline package (TSSOP).

The AD7820 is a high speed, microprocessor-compatible 8-bit ADC which uses a half-flash conversion technique to achieve a conversion time of 1.36 µs. The converter has a 0 V to +5 V analog input voltage range with a single +5 V supply.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 AD7820 is tracked and held by the input sampling circuitry, eliminating the need for an external sample-and-hold for signals with slew rates less than 100 mV/µs.The part is designed for ease of microprocessor interface with the AD7820 appearing as a memory location or I/O port without the need for external interfacing logic. All digital outputs use latched, three-state output buffer circuitry to allow direct connection to a microprocessor data bus or system input port. A non-three state overflow output is also provided to allow cascading of devices to give higher resolution.

TheAD7822/ AD7825 /AD7829are high speed, 1-, 4-, and 8-channel, microprocessor-compatible, 8-bit analog-to-digital converters with a maximum throughput of 2 MSPS. The AD7822 / AD7825 / AD7829 contain an on-chip reference of 2.5 V (2% tolerance); a track-and-hold amplifier; a 420 ns, 8-bit half-flash ADC; and a high speed parallel interface. The converters can operate from a single 3 V ± 10% and 5 V ± 10% supply.The AD7822 / AD7825 / AD7829 combine the convert start and power-down functions at one pin, that is, theCONVSTpin. This allows a unique automatic power-down at the end of a conversion to be implemented. The logic level on theCONVSTpin is sampled after the end of a conversion when anEOC(end of conversion) signal goes high. If it is logic low at that point, the ADC is powered down. The AD7822 and AD7825 also have a separate power-down pin (see the Operating Modes section).The parallel interface is designed to allow easy interfacing to microprocessors and DSPs. Using only address decoding logic, the parts are easily mapped into the microprocessor address space. TheEOCpulse allows the ADCs to be used in a stand-alone manner (see the Parallel Interface section.)The AD7822 and AD7825 are available in 20-lead and 24-lead, 0.3" wide, plastic dual in-line packages (PDIP); 20-lead and 24-lead standard small outline packages (SOIC); and 20-lead and 24-lead thin shrink small outline packages (TSSOP). The AD7829 is available in a 28-lead, 0.6" wide PDIP; a 28-lead SOIC; and a 28-lead TSSOP.PRODUCT HIGHLIGHTSFast Conversion Time. The AD7822 / AD7825 / AD7829 have a conversion time of 420 ns. Faster conversion times maximize the DSP processing time in a real-time system.Analog Input Span Adjustment. The VMIDpin allows the user to offset the input span. This feature can reduce the requirements of single-supply op amps and take into account any system offsets.FPBW (Full Power Bandwidth) of Track-and-Hold. The track-and-hold amplifier has an excellent high frequency performance. The AD7822 / AD7825 / AD7829 are capable of converting full-scale input signals up to a frequency of 10 MHz. This makes the parts ideally suited to subsampling applications.Channel Selection. Channel selection is made without the necessity of writing to the part.APPLICATIONSData acquisition systems, DSP front endsDisk drivesMobile communication systems, subsampling applications

The AD7829-1 is a high speed 8-channel, microprocessor-compatible, 8-bit analog-to-digital converter with a maximum throughput of 2 MSPS. The AD7829-1 contains an on-chip reference of 2.5 V (2% tolerance); a track/hold amplifier; a 420 ns, 8-bit half-flash ADC; and a high speed parallel interface. The converter can operate from a single 3 V ± 10% and 5 V ± 10% supply.The AD7829-1 combines the convert start and power-down functions at one pin, that is, theCONVSTpin. This allows a unique automatic power-down at the end of a conversion to be implemented. The logic level on theCONVSTpin is sampled after the end of a conversion when anEOC(end of conversion) signal goes high, and if it is logic low at that point, the ADC is powered down. The parallel interface is designed to allow easy interfacing to microprocessors and DSPs. Using only address decoding logic, the parts are easily mapped into the microprocessor address space.TheEOCpulse allows the ADCs to be used in a stand-alone manner (see the Parallel Interface section).The AD7829-1 is available in a 28-lead, wide body, small outline IC (SOIC_W) and a 28-lead thin shrink small outline package (TSSOP).PRODUCT HIGHLIGHTSFast Conversion Time. The AD7829-1 has a conversion time of 420 ns. Faster conversion times maximize the DSP processing time in a real-time system.Analog Input Span Adjustment. The VMIDpin allows the user to offset the input span. This feature can reduce the requirements of single-supply op amps and take into account any system offsets.FPBW (Full Power Bandwidth) of Track-and-Hold. The track-and-hold amplifier has excellent high frequency performance. The AD7829-1 is capable of converting fullscale input signals up to a frequency of 10 MHz, making the parts ideally suited to subsampling applications.Channel Selection. Channel selection is made without the necessity of writing to the part.APPLICATIONSData acquisition systems, DSP front endsDisk drivesMobile communication systems, subsampling applications

The AD783 is a high speed, monolithic sample-and-hold amplifier (SHA). The AD783 offers a typical acquisition time of 250 ns to 0.01%. The AD783 is specified and tested for hold mode total harmonic distortion with input frequencies up to 100 kHz. The AD783 is configured as a unity gain amplifier and uses a patented self-correcting architecture that minimizes hold mode errors and ensures accuracy over temperature. The AD783 is self-contained and requires no external components or adjustments.The AD783 retains the held value with a droop rate of 0.02 µV/µs. Excellent linearity and hold mode dc and dynamic performance make the AD783 ideal for high speed 12- and 14-bit analog-to-digital converters.The AD783 is manufactured on Analog Devices' ABCMOS process which merges high performance, low noise bipolar circuitry with low power CMOS to provide an accurate, high speed, low power SHA.The J grade device is specified for operation from 0°C to +70°C and the A grade from -40°C to +85°C. The J and A grades are available in 8-pin cerdip and SOIC packages. The military temperature range version is specified for operation from -55°C to + 125°C and is available in an 8-pin cerdip package. For details refer to theAnalog Devices Military Products Databookor AD783/883B data sheet.