LM12H458CIVF/NOPB

Single ADC 182KSPS 12Bit+Sign Parallel 44Pin PQFP Tray

The LM12458, and LM12H458 are highly integrated Data Acquisition Systems. Operating on just 5V, they combine a fully-differential self-calibrating correcting linearity and zero errors 13-bit 12-bit + sign analog-to-digital converter ADC and sample-and-hold S/H with extensive analog functions and digital functionality. Up to 32 consecutive conversions, using two"s complement format, can be stored in an internal 32-word 16-bit wide FIFO data buffer. An internal 8-word RAM can store the conversion sequence for up to eight acquisitions through the LM12H458"s eight-input multiplexer. The obsolete LM12454 has a four-channel multiplexer, a differential multiplexer output, and a differential S/H input. The LM12H458 can also operate with 8-bit + sign resolution and in a supervisory "watchdog" mode that compares an input signal against two programmable limits.

Programmable acquisition times and conversion rates are possible through the use of internal clock-driven timers. The reference voltage input can be externally generated for absolute or ratiometric operation or can be derived using the internal 2.5V bandgap reference.

All registers, RAM, and FIFO are directly addressable through the high speed microprocessor interface to either an 8-bit or 16-bit data bus. The LM12H458 includes a direct memory access DMA interface for high-speed conversion data transfer.

Additional applications information can be found in applications notes AN-906, AN-947 and AN-949.

fCLK = 5 MHz; 8 MHz, H