Small 12-bit successive-approximation ADC that samples one single-ended input at up to 1 MSPS over SPI, drawing so little that its power scales almost to zero at low sample rates (about 1 uW at 1 kSPS). The reference is the analog supply, so a clean AVDD sets the full scale, and the tiny VSSOP-8 fits next to the signal it measures. Aimed at battery and energy-harvesting systems that sample slowly but need real resolution when they do.

Pinout

Pin	Name	Type	Function
1	DVDD	power_in	Digital I/O supply voltage. Recommended range 1.65 V to 3.6 V (independent of AVDD); JESD8-7A compliant for a normal DVDD range of 1.65 V to 1.95 V. Bypass locally to GND.
2	SCLK	input	Serial clock input for the SPI-compatible interface. Used to clock out conversion data on SDO and to run the internal conversion; supports SCLK up to 16 MHz.
3	SDO	output	Serial data output. Shifts out the 12-bit conversion result MSB-first on SCLK edges while CS is asserted low. Referenced to DVDD.
4	CS	input	Active-low chip-select. The falling edge of CS samples the analog input, initiates conversion, and frames the SPI read of the conversion result.
5	AINM	input	Negative analog input of the single-ended SAR ADC. Tie to the analog ground reference; allowable range -0.3 V to +0.3 V relative to GND.
6	AINP	input	Positive analog input of the single-ended SAR ADC. Unipolar input range 0 V to AVDD; allowable range -0.3 V to AVDD+0.3 V.
7	AVDD	power_in	Analog power-supply input; also serves as the ADC reference voltage. Recommended range 1.65 V to 3.6 V. Requires a low-impedance bypass to GND for reference stability.
8	GND	power_in	Ground return for the analog and digital supplies. All analog and digital signals are referenced to this pin.

Key specifications

Parameter	Value
Type	12-bit SAR ADC
Throughput	1 MSPS
Input	Single-ended (AINP/AINM)
Interface	SPI
Reference	AVDD (supply)
Power	~1 uW at 1 kSPS
Supply	1.65-3.6 V
Package	VSSOP-8

Ordering variants

ADS7042IDCUR (VSSOP-8)
ADS7042IRUGR (X2QFN-8)

CAD (KiCad official)

Symbol: Analog_ADC:ADS7042xDCU (KiCad official)
Footprint: Package_SO:VSSOP-8_2.3x2mm_P0.5mm
3D model: VSSOP-8 (KiCad packages3D, STEP)

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

Datasheet: Texas Instruments datasheet (46 pp, sha256 96d5f335d91126fd, retrieved 2026-08-17, tier: manufacturer)
Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF