ADS1224IPWTG4



 www.ti.com SBAS286C − JUNE 2003 − REVISED JANUARY 2009
               FEATURES D 240SPS Data Rate with 4MHz Clock D 20-Bit Effective Resolution D Input Multiplexer with Four Differential D D D D D D D D D D Channels Pin-Selectable, High-Impedance Input Buffer ±5V Differential Input Range 0.0003% INL (typ), 0.0015% INL (max) Self-Calibrating Simple 2-Wire Serial Interface On-Chip Temperature Sensor Single Conversions with Standby Mode Low Current Consumption: 300µA Analog Supply: 2.7V to 5.5V Digital Supply: 2.7V to 5.5V APPLICATIONS D Hand-Held Instrumentation D Portable Medical Equipment D Industrial Process Control D Weigh Scales DESCRIPTION The ADS1224 is a 4-channel, 24-bit, delta-sigma analog-to-digital (A/D) converter. It offers excellent performance and low power in a TSSOP-20 package. The ADS1224 is well-suited for demanding, high-resolution measurements, especially in portable systems and other space-saving and power-constrained applications. A delta-sigma (∆Σ) modulator and digital filter form the basis of the A/D converter. The analog modulator has a ±5V differential input range. An input multiplexer (MUX) is used to select between four separate differential input channels. A buffer can be selected to increase the input impedance of the measurement. A simple, 2-wire serial interface provides all the necessary control. Data retrieval, self-calibration, and Standby mode are handled with a few simple waveforms. When only single conversions are needed, the ADS1224 can be quickly shut down (Standby mode) while idle between measurements to dramatically reduce the overall power consumption. Multiple ADS1224s can be connected together to create a synchronously sampling multichannel measurement system. The ADS1224 is designed to easily connect to microcontrollers, such as the MSP430. The ADS1224 supports 2.7V to 5.5V analog supplies and 2.7V to 5.5V digital supplies. Power is typically less than 1mW in 3V operation and less than 1µW during Standby mode. TEMPEN AVDD VREFP VREFN DVDD CLK AINP1 AINN1 AINP2 AINN2 Mux Buffer AINP3 AINN3 ∆Σ Modulator Digital Filter and Serial Interface SCLK DRDY/DOUT AINP4 AINN4 MUX0 MUX1 BUFEN GND Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. All trademarks are the property of their respective owners. Copyright  2003−2008, Texas Instruments Incorporated !"# "  $  % &  %  '&  ( ) (&% & $  %&&  %   $%  " %  %$ % % ( (   *) (& &%% (%  &%% *  &( %     $%) www.ti.com 

 www.ti.com SBAS286C − JUNE 2003 − REVISED JANUARY 2009 ORDERING INFORMATION(1) PRODUCT PACKAGE−LEAD PACKAGE DESIGNATOR SPECIFIED TEMPERATURE RANGE PACKAGE MARKING ADS1224 TSSOP-20 PW −40°C to +85°C ADS1224 ORDERING NUMBER TRANSPORT MEDIA, QUANTITY ADS1224IPWT Tape and Reel, 250 ADS1224IPWR Tape and Reel, 2500 (1) For the most current specification and package information, refer to our web site at www.ti.com. ABSOLUTE MAXIMUM RATINGS over operating free-air temperature range unless otherwise noted(1) ADS1224 UNIT AVDD to GND −0.3 to +6 V DVDD to GND −0.3 to +6 V 100, momentary mA Input current 10, continuous mA Analog input voltage to GND −0.3 to AVDD + 0.3 V Digital input voltage to GND −0.3 to DVDD + 0.3 V +150 °C Operating Temperature Range −55 to +125 °C Storage Temperature Range −60 to +150 °C Maximum Junction Temperature Lead Temperature (soldering, 10s) +300 °C (1) Stresses above these ratings may cause permanent damage. Exposure to absolute maximum conditions for extended periods may degrade device reliability. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those specified is not implied. 2 This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage. ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more susceptible to damage because very small parametric changes could cause the device not to meet its published specifications. 

 www.ti.com SBAS286C − JUNE 2003 − REVISED JANUARY 2009 ELECTRICAL CHARACTERISTICS All specifications at TA = −40°C to +85°C, AVDD = +5V, DVDD = +5V, fCLK = 2MHz, and VREF = +2.5V, unless otherwise noted. PARAMETER TEST CONDITIONS MIN TYP MAX UNIT Analog Input Full-scale input voltage Absolute input voltage Differential input impedance Common-mode input impedance ±2VREF AINP − AINN V Buffer off; AINP, AINN with respect to GND GND − 0.1 AVDD + 0.1 Buffer on; AINP, AINN with respect to GND GND + 0.05 AVDD − 1.5 V V Buffer off; fCLK = 2MHz 2.7 MΩ Buffer on; fCLK = 2MHz 1.2 GΩ Buffer off; fCLK = 2MHz 5.4 MΩ 120 (fCLK/2MHz) Bits SPS(1) % of FSR(2) System Performance Resolution No missing codes 24 Data rate Integral nonlinearity (INL) Offset error Offset error drift Offset error match Gain error Gain error drift Gain error match Common-mode rejection Analog power-supply rejection Digital power-supply rejection Buffer off, Differential input signal, end point fit 0.0003 Buffer on, Differential input signal, end point fit 0.0006 0.0015 % of FSR 100 µV Buffer off 20 Buffer on 20 µV Buffer off 0.2 µV/°C Buffer on 0.2 µV/°C 20 100 µV Buffer off 0.004 0.025 % Buffer on 0.008 % Buffer off 0.00003 % of FSR/°C Buffer on 0.00006 % of FSR/°C Between channels 0.0005 % Between channels Buffer off, at DC 90 110 dB Buffer on, at DC 90 110 dB Buffer off, at DC, ± 10% ∆ in AVDD 95 dB Buffer on, at DC, ± 10% ∆ in AVDD 95 dB Buffer off, at DC, DVDD = 2.7V to 5.5V 85 dB Buffer on, at DC, DVDD = 2.7V to 5.5V 85 dB 0.8 ppm of FSR, rms 106 mV 360 µV/°C Noise Temperature Sensor Temperature sensor voltage TA = 25°C Temperature sensor coefficient Voltage Reference Input AVDD(3) V GND − 0.1 VREFP − 0.5 V Buffer off VREFN + 0.5 AVDD + 0.1 V Negative reference input Buffer on GND + 0.05 VREFP − 0.5 V Positive reference input Buffer on VREFN + 0.5 AVDD − 1.5 Voltage reference impedance fCLK = 2MHz Reference input voltage Negative reference input VREF = VREFP − VREFN Buffer off Positive reference input 0.5 2.5 500 V kΩ (1) SPS = samples per second. (2) FSR = full-scale range = 4VREF. (3) It will not be possible to reach the digital output full-scale code when VREF > AVDD/2. 3 

 www.ti.com SBAS286C − JUNE 2003 − REVISED JANUARY 2009 ELECTRICAL CHARACTERISTICS (continued) All specifications at TA = −40°C to +85°C, AVDD = +5V, DVDD = +5V, fCLK = 2MHz, and VREF = +2.5V, unless otherwise noted. PARAMETER TEST CONDITIONS MIN TYP MAX UNIT 0.8 DVDD DVDD + 0.1 V GND − 0.1 0.2 DVDD V Digital Input/Output Logic levels VIH VIL VOH VOL IOH = 1mA IOL = 1mA 0.8 DVDD V Input leakage CLK frequency (fCLK) 0.2 DVDD V ±10 µA 8 MHz 30 70 % AVDD 2.7 5.5 V DVDD 2.7 5.5 CLK duty cycle Power Supply AVDD current DVDD current Total power dissipation V Standby mode