4-Channel, 1.5 MSPS, 10-Bit and 12-Bit Parallel ADCs with a Sequencer AD7933/AD7934 FEATURES FUNCTIONAL BLOCK DIAGRAM V AGND Throughput rate: 1.5 MSPS DD Specified for V of 2.7 V to 5.25 V DD AD7933/AD7934 V REFIN/ Low power V REFOUT 2.5V 6 mW maximum at 1.5 MSPS with 3 V supplies VREF 13.5 mW maximum at 1.5 MSPS with 5 V supplies V 0 IN CLKIN 12-/10-BIT 4 analog input channels with a sequencer SAR ADC I/P CONVST T/H AND MUX Software configurable analog inputs CONTROL BUSY V 3 4-channel single-ended inputs IN 2-channel fully differential inputs 2-channel pseudo differential inputs SEQUENCER Accurate on-chip 2.5 V reference 0.2% maximum 25C, 25 ppm/C maximum (AD7934) PARALLEL INTERFACE/CONTROL REGISTER V DRIVE 70 dB SINAD at 50 kHz input frequency No pipeline delays High speed parallel interfaceword/byte modes Full shutdown mode: 2 A maximum DB0 DB11 CS RD WR W/B DGND 28-lead TSSOP package Figure 1. GENERAL DESCRIPTION The AD7933/AD7934 are 10-bit and 12-bit, high speed, low These parts use advanced design techniques to achieve very low power, successive approximation (SAR) analog-to-digital power dissipation at high throughput rates. They also feature converters (ADCs). The parts operate from a single 2.7 V to flexible power management options. An on-chip control 5.25 V power supply and feature throughput rates up to 1.5 MSPS. register allows the user to set up different operating conditions, The parts contain a low noise, wide bandwidth, differential track- including analog input range and configuration, output coding, and-hold amplifier that handles input frequencies up to 50 MHz. power management, and channel sequencing. PRODUCT HIGHLIGHTS The AD7933/AD7934 feature four analog input channels with a channel sequencer that allows a preprogrammed selection of 1. High throughput with low power consumption. channels to be sequentially converted. These parts can accept 2. Four analog inputs with a channel sequencer. either single-ended, fully differential, or pseudo differential 3. Accurate on-chip 2.5 V reference. analog inputs. 4. Single-ended, pseudo differential or fully differential analog inputs that are software selectable. The conversion process and data acquisition are controlled 5. Single-supply operation with VDRIVE function. using standard control inputs that allow for easy interfacing to The VDRIVE function allows the parallel interface to connect microprocessors and DSPs. The input signal is sampled on the directly to 3 V or 5 V processor systems independent of V . DD falling edge of CONVST, and the conversion is also initiated at 6. No pipeline delay. this point. CONVST 7. Accurate control of the sampling instant via a The AD7933/AD7934 has an accurate on-chip 2.5 V reference input and once-off conversion control. that is used as the reference source for the analog-to-digital Table 1. Related Devices conversion. Alternatively, this pin can be overdriven to provide Device No. of Bits No. of Channels Speed an external reference. AD7938/AD7939 12/10 8 1.5 MSPS AD7938-6 12 8 625 kSPS AD7934-6 12 4 625 kSPS Rev. B 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 One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No Tel: 781.329.4700 www.analog.com license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Fax: 781.461.3113 20052007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. 03713-001AD7933/AD7934 TABLE OF CONTENTS Features .............................................................................................. 1 Converter Operation.................................................................. 17 Functional Block Diagram .............................................................. 1 ADC Transfer Function............................................................. 17 General Description ......................................................................... 1 Typical Connection Diagram ................................................... 18 Product Highlights ........................................................................... 1 Analog Input Structure.............................................................. 18 Revision History ............................................................................... 2 Analog Inputs ............................................................................. 19 Specifications..................................................................................... 3 Analog Input Selection .............................................................. 21 AD7933 Specifications................................................................. 3 Reference ..................................................................................... 22 AD7934 Specifications................................................................. 5 Parallel Interface......................................................................... 23 Timing Specifications .................................................................. 7 Power Modes of Operation ....................................................... 26 Absolute Maximum Ratings............................................................ 8 Power vs. Throughput Rate....................................................... 27 ESD Caution.................................................................................. 8 Microprocessor Interfacing....................................................... 27 Pin Configuration and Function Descriptions............................. 9 Application Hints ........................................................................... 29 Typical Performance Characteristics ........................................... 11 Grounding and Layout .............................................................. 29 Terminology .................................................................................... 13 Evaluating the AD7933/AD7934 Performance...................... 29 Control Register.............................................................................. 15 Outline Dimensions....................................................................... 30 Sequencer Operation ................................................................. 16 Ordering Guide .......................................................................... 30 Circuit Information........................................................................ 17 REVISION HISTORY 2/07Rev. A to Rev B Changes to Timing Specifications.................................................. 7 Changes to Figure 13...................................................................... 12 12/05Rev. 0 to Rev. A Replaced Figures.................................................................Universal Changes to General Description .................................................... 1 Changes to Product Highlights....................................................... 1 Added Table 1.................................................................................... 1 Changes to Specifications Section.................................................. 3 Changes to Table 5............................................................................ 9 Changes to Terminology Section.................................................. 13 Changes to Control Register Section ........................................... 15 Changes to Circuit Information Section ..................................... 17 Changes to Application Hints Section......................................... 29 1/05Revision 0: Initial Version Rev. B Page 2 of 32