The ADS1120 is a precision, 16-bit, analog-to-digital converter (ADC) that offers many integrated features to reduce system cost and component count in applications measuring small sensor signals. The device features two differential or four single-ended inputs through a flexible input multiplexer (MUX), a low-noise, programmable gain amplifier (PGA), two programmable excitation current sources, a voltage reference, an oscillator, a low-side switch, and a precision temperature sensor.
The device can perform conversions at data rates up to 2000 samples-per-second (SPS) with single-cycle settling. At 20 SPS, the digital filter offers simultaneous 50-Hz and 60-Hz rejection for noisy industrial applications. The internal PGA offers gains up to 128 V/V. This PGA makes the ADS1120 ideally-suited for applications measuring small sensor signals, such as resistance temperature detectors (RTDs), thermocouples, thermistors, and bridge sensors. The device supports measurements of pseudo- or fully-differential signals when using the PGA. Alternatively, the device can be configured to bypass the internal PGA while still providing high input impedance and gains up to 4 V/V, allowing for single-ended measurements.
Power consumption is as low as 120 µA when operating in duty-cycle mode with the PGA disabled. The ADS1120 is offered in a leadless VQFN-16 or a TSSOP-16 package and is specified over a temperature range of –40°C to +125°C.
PART NUMBER | PACKAGE | BODY SIZE (NOM) |
---|---|---|
ADS1120 | VQFN (16) | 3.50 mm × 3.50 mm |
TSSOP (16) | 5.00 mm × 4.40 mm |
Changes from B Revision (January 2015) to C Revision
Changes from A Revision (January 2014) to B Revision
Changes from * Revision (August 2013) to A Revision
PIN | ANALOG OR DIGITAL INPUT/OUTPUT |
DESCRIPTION(1) | ||
---|---|---|---|---|
NAME | NO. | |||
RVA | PW | |||
AIN0/REFP1 | 9 | 11 | Analog input | Analog input 0, positive reference input 1 |
AIN1 | 8 | 10 | Analog input | Analog input 1 |
AIN2 | 5 | 7 | Analog input | Analog input 2 |
AIN3/REFN1 | 4 | 6 | Analog input | Analog input 3, negative reference input 1. Internal low-side power switch connected between AIN3/REFN1 and AVSS. |
AVDD | 10 | 12 | Analog | Positive analog power supply |
AVSS | 3 | 5 | Analog | Negative analog power supply |
CLK | 1 | 3 | Digital input | External clock source pin. Connect to DGND if not used. |
CS | 16 | 2 | Digital input | Chip select; active low. Connect to DGND if not used. |
DGND | 2 | 4 | Digital | Digital ground |
DIN | 14 | 16 | Digital input | Serial data input |
DOUT/DRDY | 13 | 15 | Digital output | Serial data output combined with data ready; active low |
DRDY | 12 | 14 | Digital output | Data ready, active low. Leave unconnected or tie to DVDD using a weak pull-up resistor if not used. |
DVDD | 11 | 13 | Digital | Positive digital power supply |
REFN0 | 6 | 8 | Analog input | Negative reference input 0 |
REFP0 | 7 | 9 | Analog input | Positive reference input 0 |
SCLK | 15 | 1 | Digital input | Serial clock input |
Thermal pad | — | — | Thermal power pad. Do not connect or only connect to AVSS. |