Features • I 2C-Compatible 2-wire Interface which supports standard (100kHz), fast (400kHz), and high speed (3.4MHz) modes • Extended power supply range (+2.7V to +5.5V) • Up to nine pin-selectable chip addresses (MSOP-8 only) • Out-of-range Alert Function • Automatic Power-down mode while not converting • Very small TSOT-6 and MSOP-8 packages • ±8kV HBM ESD protection (SDA, SCL) Description These converters are low-power, monolithic, 12-bit, analog-to-digital converters (ADCs) that operates from a +2.7 to 5.5V supply. The converter is based upon a successive approximation register architecture with an internal track-and-hold circuit that can handle input frequencies up to 11MHz. These converters operate from a single supply which also serves as the reference. The device features an I 2C-compatible serial interface that operates in all three speed modes, including high speed mode (3.4MHz). The ADC121C021's Alert feature provides an interrupt that is activated when the analog input violates a programmable upper or lower limit value. The device features an automatic conversion mode, which frees up the controller and I 2C interface. In this mode, the ADC continuously monitors the analog input for an "out-of-range" condition and provides an interrupt if the measured voltage goes out-of-range. The ADC121C021 comes in two packages: a small TSOT-6 package with an alert output, and an MSOP-8 package with an alert output and two address selection inputs. The ADC121C027 comes in a small TSOT-6 package with an address selection input. The ADC121C027 provides three pin-selectable addresses while the MSOP-8 version of the ADC121C021 provides nine pin-selectable addresses. Pin-compatible alternatives to the TSOT-6 options are available with additional address options. Normal power consumption using a +3V or +5V supply is 0.26mW or 0.78mW, respectively. The automatic power-down feature reduces the power consumption to less than 1µW while not converting. Operation over the industrial temperature range of −40°C to +105°C is guaranteed. Their low power consumption and small packages make this family of ADCs an excellent choice for use in battery operated equipment. The ADC121C021 and ADC121C027 are part of a family of pin-compatible ADCs that also provide 8 and 10 bit resolution. For 8-bit ADCs see the ADC081C021 and ADC081C027. For 10-bit ADCs see the ADC101C021 and ADC101C027. Key Specification Resolution 12 bits; no missing codes Conversion Time 1µs (typ) INL & DNL ±1 LSB (max) (up to 22ksps) Throughput Rate 188.9ksps (max) Power Consumption (at 22ksps) 3V Supply 0.26 mW (typ) 5V Supply 0.78 mW (typ) Applications • System Monitoring • Peak Detection • Portable Instruments • Medical Instruments • Test Equipment

Typical Application Circuit MY BRIEFCASE                                       Click any "Briefcase" icon to add an item

Typical Application click for larger image Typical Application Circuit	Block Diagram click for larger image Block Diagram
Typical Performance click for larger image INL vs. CODE - Va=3.0V

Datasheet

Title		Size	Date	Other Language
	ADC121C021/ADC121C027 I 2 C-Compatible, 12-Bit Analog-to-Digital Converter with Alert Function	798 Kbytes	27-Apr-09

Featured Application Notes

Title		Size	Date	Other Language
	AN-1261: Application Note 1261 Power Supply Effects on Noise Performance	78 Kbytes	16-Mar-07	中文

More Application Notes

Title		Size	Date	Other Language
	AN-1261: Application Note 1261 Power Supply Effects on Noise Performance	78 Kbytes	16-Mar-07	中文

Reliability Metrics

Part Number	Process	EFR Reject	EFR Sample Size	PPM	LTA Rejects	LTA Device Hours	FITS	MTTF (Hours)
ADC121C027CIMK	CMOS7	0	18406	0	0	1089000	4	309006723
ADC121C027CIMKX	CMOS7	0	18406	0	0	1089000	4	309006723

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.

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