AD7843: Touch Screen Digitizer Data Sheet (Rev. B)10/28/2000271 kB
Features and Benefits
- 4-wire touch screen interface
- Specified throughput rate of 125 kSPS
- Low power consumption: 1.37 mW max at 125 kSPS with VCC = 3.6 V
- Single supply, VCC of 2.2 V to 5.25 V
- Ratiometric conversion
- High speed serial interface
- Programmable 8-bit or 12-bit resolution
- 2 auxiliary analog inputs
- Shutdown mode: 1 µA max
- 16-lead QSOP and TSSOP packages
The AD7843 is a 12-bit successive-approximation ADC with a synchronous serial interface and low on resistance switches for driving touch screens. The part operates from a single 2.2 V to 5.25 V power supply and features throughput rates greater than 125 kSPS. The external reference applied to the AD7843 can be varied from 1 V to +VCC, while the analog input range is from 0 V to VREF. The device includes a shutdown mode that reduces the current consumption to less than 1 µA. This part is available in a 16-lead 0.15" Quarter Size Outline (QSOP) package and a 16-lead Thin Shrink Small Outline (TSSOP) package.
Also see the AD7843 sister part, which is the AD7873. This part is similar to the AD7843 but has added functionality such as an on-chip temperature sensor (-40°C to + 85°C), on-chip 2.5 V reference and direct battery and touch-pressure measurement.
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Documentation & Resources
UG-062: Evaluation Board for AD7843/AD7873 Resistive Touch Screen Controllers12/2/2009334 kB
Designing Power Supplies for High Speed ADC2/1/2012
The PDA Challenge—Met by the AD7873 Resistive-Touch-Screen Controller ADC8/1/2001 Analog Dialogue
Software & Systems Requirements
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Support & Discussions
Sample & Buy
See our Ordering FAQs for answers to questions about online orders, payment options and more.
Buy Now Pricing
(**) Displayed Buy Now Price and Price Range is based on small quantity orders.
(*)The 1Ku list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.
Please see the latest communication from our CCO regarding lead times.
Selecting the Sample button above will redirect to the third-party ADI Sample Site. The part selected will carry over to your cart on this site once logged in. Please create a new account there if you have never used the site before. Contact SampleSupport@analog.com with any questions regarding this Sample Site.