The ADuC816 is a complete smart transducer front-end, integratingtwo high-resolution sigma-delta ADCs, an 8-bit MCU,and program/data Flash/EE Memory on a single chip. This lowpower device accepts low-level signals directly from a transducer.

The two independent ADCs (Primary and Auxiliary) include atemperature sensor and a PGA (allowing direct measurement oflow-level signals). The ADCs with on-chip digital filtering areintended for the measurement of wide dynamic range, lowfrequency signals, such as those in weigh scale, strain gauge,pressure transducer, or temperature measurement applications.The ADC output data rates are programmable and the ADCoutput resolution will vary with the programmed gain andoutput rate.

The device operates from a 32 kHz crystal with an on-chip PLLgenerating a high-frequency clock of 12.58 MHz. This clock is,in turn, routed through a programmable clock divider from whichthe MCU core clock operating frequency is generated. Themicrocontroller core is an 8052 and therefore 8051-instructionset-compatible.The microcontroller core machine cycle consistsof 12 core clock periods of the selected core operating frequency.8 Kbytes of nonvolatile Flash/EE program memory are providedon-chip. 640 bytes of nonvolatile Flash/EE data memory and256 bytes RAM are also integrated on-chip.

The ADuC816 also incorporates additional analog functionalitywith a 12-bit DAC, current sources, power supply monitor,and a bandgap reference. On-chip digital peripherals include awatchdog timer, time interval counter, three timers/counters,and three serial I/O ports (SPI, UART, and I²C-compatible).

On-chip factory firmware supports in-circuit serial download anddebug modes (via UART), as well as single-pin emulation modevia the EA pin.

The part operates from a single 3 V or 5 V supply. When operatingfrom 3 V supplies, the power dissipation for the part is below10 mW. The ADuC816 is housed in a 52-lead MQFP package.The part operates from a single 3 V or 5 V supply. When operatingfrom 3 V supplies, the power dissipation for the part is below10 mW. The ADuC816 is housed in 52-lead MQFP and 56-leadLFCSP packages.

Applications

• Intelligent Sensors (IEEE1451.2-Compatible)
• Weigh Scales
• Portable Instrumentation
• Pressure Transducers
• 4–20 mA Transmitters

At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.