2 4-Channel, 10- and 12-Bit ADCs with I C- Compatible Interface in 16-Lead TSSOP AD7993/AD7994 FEATURES FUNCTIONAL BLOCK DIAGRAM 10- and 12-bit ADC with fast conversion time: 2 s typ V AGND REF CONVST DD IN 4 single-ended analog input channels AD7993/AD7994 Specified for V of 2.7 V to 5.5 V DD 10-/12-BIT V 1 IN Low power consumption SUCCESSIVE CONTROL T/H APPROXIMATION LOGIC V 2 IN Fast throughput rate: 188 kSPS I/P ADC MUX V 3 IN Temperature range:40C to +125C V 4 OSCILLATOR IN Sequencer operation Automatic cycle interval mode CONVERSION 2 I C-compatible serial interface DATA LIMIT RESULT LOW REGISTER REGISTER CH1CH4 2 I C interface supports standard, fast, and high speed modes CONFIGURATION ALERT/ Out-of-range indicator/alert function REGISTER BUSY DATA LIMIT HIGH Pin-selectable addressing via AS REGISTER CH1CH4 ALERT STATUS Shutdown mode: 1 A max REGISTER 16-lead TSSOP package HYSTERESIS CYCLE TIMER REGISTER CH1CH4 See AD7998 and AD7992 for 8-channel and 2-channel REGISTER equivalent devices, respectively. AS SCL 2 I C INTERFACE SDA GENERAL DESCRIPTION AGND The AD7993/AD7994 are 4-channel, 10- and 12-bit, low power, 2 successive approximation ADCs with an I C-compatible inter- Figure 1. face. The parts operate from a single 2.7 V to 5.5 V power On-chip limit registers can be programmed with high and low supply and feature a 2 s conversion time. The parts contain a limits for the conversion result, and an open-drain, out-of- 4-channel multiplexer and track-and-hold amplifier that can range indicator output (ALERT) becomes active when the handle input frequencies up to 11 MHz. 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. 2 compatible with I C interfaces. Each part comes in two versions, PRODUCT HIGHLIGHTS AD7993-0/AD7994-0 and AD7993-1/AD7994-1, and each 2 2 1. 2 s conversion time with low power consumption. version allows for at least two different I C addresses. The I C interface on the AD7993-0/AD7994-0 supports standard and 2 2. I C-compatible serial interface with pin-selectable 2 2 fast I C interface modes. The I C interface on the AD7993-1/ addresses. Two AD7993/AD7994 versions allow five 2 AD7994-1 supports standard, fast, and high speed I C 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 pin, CONVST 1 A max when in shutdown mode. 2 by a command mode where conversions occur across I C 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 REF pin and can be in the range of 1.2 V to 6. One-shot and automatic conversion rates. IN V . This allows the widest dynamic input range to the ADC. DD 7. Registers can store minimum and maximum conversion results. Rev. 0 Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Specifications subject to change without notice. No license is granted by implication Tel: 781.329.4700 www.analog.com or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. Fax: 781.326.8703 2004 Analog Devices, Inc. All rights reserved. 03472-0-001AD7993/AD7994 TABLE OF CONTENTS Serial Interface ................................................................................ 23 AD7993 Specifications..................................................................... 3 Serial Bus Address...................................................................... 23 AD7994 Specifications..................................................................... 5 2 Writing to the AD7993/AD7994 .................................................. 24 I C Timing Specifications................................................................ 7 Writing to the Address Pointer Register for a Subsequent Absolute Maximum Ratings............................................................ 9 Read.............................................................................................. 24 ESD Caution.................................................................................. 9 Writing a Single Byte of Data to the Alert Status Register or Pin Configuration and Pin Function Descriptions.................... 10 Cycle Register.............................................................................. 24 Terminology .................................................................................... 11 Writing Two Bytes of Data to a Limit or Hysteresis Register ........................................................................................ 24 Typical Performance Characteristics ........................................... 12 Reading Data from the AD7993/AD7994................................... 26 Circuit Information........................................................................ 15 Alert/Busy Pin................................................................................. 27 Converter Operation.................................................................. 15 SMBus Alert ................................................................................ 27 Typical Connection Diagram ................................................... 16 Busy.............................................................................................. 27 Analog Input ............................................................................... 16 Placing the AD7993-1/AD7994-1 into High Speed Mode ... 27 Internal Register Structure ............................................................ 18 The Address Select (AS) Pin..................................................... 27 Address Pointer Register ........................................................... 18 Modes of Operation ....................................................................... 28 Configuration Register .............................................................. 19 Mode 1Using the CONVST Pin ........................................... 28 Conversion Result Register ....................................................... 20 Mode 2Command Mode....................................................... 29 Limit Registers ............................................................................ 20 Mode 3Automatic Cycle Interval Mode.............................. 30 Alert Status Register................................................................... 21 Outline Dimensions ....................................................................... 31 Cycle Timer Register.................................................................. 22 Ordering Guide .......................................................................... 31 Sample Delay and Bit Trial Delay............................................. 22 2 Related Parts in I C-Compatible ADC Product Family........ 31 REVISION HISTORY 10/04Revision 0: Initial Version Rev. 0 Page 2 of 32