LM12458CIV

ADCs/DACs - Special Purpose Overview

The LM12458CIV is a highly integrated 12-bit plus sign data acquisition system manufactured by Texas Instruments (formerly National Semiconductor). It combines a fully-differential self-calibrating analog-to-digital converter, sample-and-hold circuit, and an eight-channel multiplexer. The device features a 32-word FIFO buffer and internal instruction RAM for event sequencing. Operating on a single 3V to 5.5V supply, it supports 8-bit or 12-bit plus sign resolution with throughput rates up to 140k samples per second at 8MHz clock speeds. It includes a direct memory access interface and programmable acquisition times.

ADCs/DACs - Special Purpose Feature Summary

• Integrated 13-bit (12-bit + sign) SAR ADC with built-in self-calibration for linearity and zero error correction
• Eight-channel analog multiplexer with differential output and internal sample-and-hold
• 32-word conversion FIFO and 8-word instruction RAM for automated acquisition sequences
• Supports 8-bit or 12-bit plus sign modes, including a 'watchdog' comparison mode
• Compatible with 8-bit or 16-bit microprocessor/DSP buses via TRI-STATE buffers

ADCs/DACs - Special Purpose Applications

• Data logging systems requiring multi-channel acquisition
• Industrial instrumentation and process control
• Energy management monitoring
• Inertial guidance systems

ADCs/DACs - Special Purpose Procurement Notes

Verify component authenticity as the LM12458 series originates from National Semiconductor, now part of Texas Instruments. Confirm package integrity for the V44A PLCC variant. Check for RoHS compliance status if required for modern manufacturing standards. Ensure compatibility with existing 5V logic levels. Review datasheet revision history for any electrical characteristic updates.

ADCs/DACs - Special Purpose Selection Notes

Select the LM12458CIV for applications requiring up to eight single-ended or differential inputs with moderate speed requirements. Choose this over the LM12H458 if a 5MHz maximum clock frequency is sufficient, as it offers lower power consumption. Ensure the design accommodates the V44A PLCC package footprint. Verify that the system can support the required 8-bit or 16-bit bus width configuration via the BW pin.

ADCs/DACs - Special Purpose Part Context

The LM12458 is part of the LM12454/LM12458/LM12H458 family. The LM12454 is obsolete and features only four channels. The LM12H458 is the high-speed variant supporting up to 8MHz clocks. The LM12458 provides a balance of performance and power, operating at up to 5MHz. All variants share similar functionality but differ in channel count and maximum clock speed.

ADCs/DACs - Special Purpose Replacement Considerations

No direct public substitute part numbers are listed in the provided documentation. The LM12H458 serves as a higher-performance alternative within the same family. Designers should verify pinout and register compatibility when considering cross-family replacements.