Datasheet AD7993, AD7994 (Analog Devices)

4-Channel, 10- and 12-Bit ADCs with I2C- Compatible Interface in 16-Lead TSSOP AD7993/AD7994 FEATURES FUNCTIONAL BLOCK DIAGRAM 10- and 12-bit ADC with fast conversion time: 2 µs typ VDD AGND REF CONVST IN 4 single-ended analog input channels Specified for V AD7993/AD7994 DD of 2.7 V to 5.5 V 10-/12-BIT Low power consumption VIN1 SUCCESSIVE CONTROL T/H Fast throughput rate: 188 kSPS APPROXIMATION LOGIC VIN2 I/P ADC Temperature range:−40°C to +125°C V MUX IN3 V OSCILLATOR Sequencer operation IN4 Automatic cycle interval mode CONVERSION I2C®-compatible serial interface DATALOWLIMIT RESULT I2C interface supports standard, fast, and high speed modes REGISTER CH1–CH4 REGISTER Out-of-range indicator/alert function CONFIGURATION ALERT/ REGISTER DATA BUSY Pin-selectable addressing via AS HIGHLIMIT REGISTER CH1–CH4 Shutdown mode: 1 µA max ALERT STATUS REGISTER 16-lead TSSOP package HYSTERESIS See AD7998 an d AD7992 for 8-channel and 2-channel CYCLE TIMER REGISTER CH1–CH4 REGISTER equivalent devices, respectively. AS SCL GENERAL DESCRIPTION I2C INTERFACE SDA
The AD7993/AD7994 are 4-channel, 10- and 12-bit, low power,
AGND
03472-0-001 successive approximation ADCs with an I2C-compatible inter- Figure 1. face. The parts operate from a single 2.7 V to 5.5 V power supply and feature a 2 µs conversion time. The parts contain a On-chip limit registers can be programmed with high and low 4-channel multiplexer and track-and-hold amplifier that can limits for the conversion result, and an open-drain, out-of- handle input frequencies up to 11 MHz. range indicator output (ALERT) becomes active when the programmed high or low limits are violated by the conversion The AD7993/AD7994 provide a 2-wire serial interface that is result. This output can be used as an interrupt. compatible with I2C interfaces. Each part comes in two versions,
PRODUCT HIGHLIGHTS
AD7993-0/AD7994-0 and AD7993-1/AD7994-1, and each version allows for at least two different I2C addresses. The I2C 1. 2 µs conversion time with low power consumption. interface on the AD7993-0/AD7994-0 supports standard and 2. I2C-compatible serial interface with pin-selectable fast I2C interface modes. The I2C interface on the AD7993-1/ addresses. Two AD7993/AD7994 versions allow five AD7994-1 supports standard, fast, and high speed I2C interface AD7993/AD7994 devices to be connected to the same modes. serial bus. The AD7993/AD7994 normally remain in a shutdown state 3. The parts feature automatic shutdown while not converting while not converting, and power up only for conversions. The to maximize power efficiency. Current consumption is conversion process can be controlled using the CONVST pin, 1 µA max when in shutdown mode. by a command mode where conversions occur across I2C write 4. Reference can be driven up to the power supply. operations, or an automatic conversion interval mode selected through software control. 5. Out-of-range indicator that can be software disabled or enabled. The AD7993/AD7994 require an external reference that should be applied to the REFIN pin and can be in the range of 1.2 V to 6. One-shot and automatic conversion rates. VDD. This allows the widest dynamic input range to the ADC. 7. Registers can store minimum and maximum conversion results.
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Document Outline FEATURES GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAM PRODUCT HIGHLIGHTS AD7993 SPECIFICATIONS AD7994 SPECIFICATIONS I2C TIMING SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS ESD CAUTION PIN CONFIGURATION AND PIN FUNCTION DESCRIPTIONS TERMINOLOGY TYPICAL PERFORMANCE CHARACTERISTICS CIRCUIT INFORMATION CONVERTER OPERATION TYPICAL CONNECTION DIAGRAM ANALOG INPUT INTERNAL REGISTER STRUCTURE ADDRESS POINTER REGISTER CONFIGURATION REGISTER CONVERSION RESULT REGISTER LIMIT REGISTERS ALERT STATUS REGISTER CYCLE TIMER REGISTER SAMPLE DELAY AND BIT TRIAL DELAY SERIAL INTERFACE SERIAL BUS ADDRESS WRITING TO THE AD7993/AD7994 WRITING TO THE ADDRESS POINTER REGISTER FOR A SUBSEQUENT REA WRITING A SINGLE BYTE OF DATA TO THE ALERT STATUS REGISTER O WRITING TWO BYTES OF DATA TO A LIMIT OR HYSTERESIS REGISTER READING DATA FROM THE AD7993/AD7994 ALERT/BUSY PIN SMBus ALERT BUSY PLACING THE AD7993-1/AD7994-1 INTO HIGH SPEED MODE THE ADDRESS SELECT (AS) PIN MODES OF OPERATION MODE 1—USING THE CONVST PIN MODE 2—COMMAND MODE MODE 3—AUTOMATIC CYCLE INTERVAL MODE OUTLINE DIMENSIONS ORDERING GUIDE RELATED PARTS IN I2C-COMPATIBLE ADC PRODUCT FAMILY