Features Three operating modes: 12-bit + sign, 8-bit + sign, and "watchdog" Single-ended or differential inputs Built-in Sample-and-Hold and 2.5V bandgap reference Instruction RAM and event sequencer 8-channel multiplexer 32-word conversion FIFO Programmable acquisition times and conversion rates Self-calibration and diagnostic mode 8- or 16-bit wide data bus microprocessor or DSP interface Description 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 LM12(H)458's eight-input multiplexer. The obsolete LM12454 has a four-channel multiplexer, a differential multiplexer output, and a differential S/H input. The LM12(H)458 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 LM12(H)458 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. Key Specification (fCLK = 5 MHz; 8 MHz, H) Resolution 12-bit + sign or 8-bit + sign 13-bit conversion time 8.8 µs, 5.5 µs (H) (max) 9-bit conversion time 4.2 µs, 2.6 µs (H) (max) 13-bit Through-put rate 88k samples/s (min),140k samples/s (H) (min) Comparison time ("watchdog" mode) 2.2 µs (max),1.4 µs (H) (max) ILE ±1 LSB (max) VIN range GND to VA+ Power Consumption 30 mW, 34 mW (H) (max) Stand-by mode 50 µW (typ) Single supply 3V to 5.5V Applications Data Logging Instrumentation Process Control Energy Management Inertial Guidance

Also Recommended LM12H458▲ Higher Speed (5.5us) LM12L458▲ Lower Voltage/Power (3.3V)

	Block Diagram click for larger image
Typical Performance click for larger image

Datasheets

Title		Size	Date	Other Language
	LM12458 12-Bit Plus Sign Data Acquisition System with Self-Calibration	1195 Kbytes	16-Feb-06

Application Notes

Title		Size	Date	Other Language
	AN-906: Application Note 906	561 Kbytes	5-Aug-95	日本語
	AN-949: Application Note 949	579 Kbytes	5-Aug-95
	AN-947: Application Note 947	279 Kbytes	5-Aug-95

Part Number(s) (NSID)	Top View	Availability	Current Reported Stock	Budgetary Pricing	Pack Size
LM12458CIV/NOPB LM12458CIV RoHS Status	PLCC	Full production Lead Time: 6 weeks	Distributor Region Qty ARROW Worldwide 166 AVNET-EM Worldwide 125 DIGI-KEY Worldwide 144 FARNELL Europe and Asia 41 MOUSER Worldwide 23 RS COMPONENTS Worldwide 11 TAYLOR Americas 166	$14.40 each at 1K+ pcs	rail of 25

Obsolete Versions

Obsolete Part	Alternate Part or Supplier	Source	Last Time Buy Date
LM12458CIVF	NONE	NATIONAL SEMICONDUCTOR	05 Sep 2006
LM12458EVAL	NONE	NONE	07 Jun 2000
LM12458MEL/883	NONE	NONE	03 Mar 2004

All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

Moisture Sensitivity Level Data for LM12458.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

National's certificate of product compliance for LM12458 is located at RoHS Status.

Part Number(s) (NSID)	Weight (milligrams)	Type	Pins	MSL Rating	Peak Reflow	RoHS Status	CAD Symbols	Models	Package Marking Format
LM12458CIV/NOPB LM12458CIV	2214.83 2220	PLCC	44	3 2A	245 220	Detail	N/A	N/A	NSUZXYYTTE# LM12458CIV

All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

Moisture Sensitivity Level Data for LM12458.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

National's certificate of product compliance for LM12458 is located at RoHS Status.

CAD Symbols and Models N/A

Models N/A

Reliability Metrics

Part Number	Process	EFR Reject	EFR Sample Size	PPM	LTA Rejects	LTA Device Hours	FITS	MTTF (Hours)
LM12458CIV	CS150	1	16290	62	0	1157500	4	328443785

Note: The Early Failure Rates (EFR) were calculated as point estimate PPM based on rejects and sample size for EFR. The Long Term Failure Rates were calculated at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress temperature of 150°C to an application temperature of 55°C.

For more information on Reliability Metrics, please click here.

All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

Moisture Sensitivity Level Data for LM12458.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

National's certificate of product compliance for LM12458 is located at RoHS Status.

Obsolete Versions

Obsolete Part	Alternate Part or Supplier	Source	Last Time Buy Date
LM12458CIVF	NONE	NATIONAL SEMICONDUCTOR	05 Sep 2006
LM12458EVAL	NONE	NONE	07 Jun 2000
LM12458MEL/883	NONE	NONE	03 Mar 2004