ADI AD7843ARUZ

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. The AD7843 features on-board switches. This, coupled with low power and high speed operation, make this device ideal for battery-powered systems such as personal digital assistants with resistive touch screens, and other portable equipment. The part is available in a 16-lead 0.15" quarter size outline package (QSOP) and a 16-lead thin shrink small outline package (TSSOP).

• 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

• Personal digital assistants
• Smart hand-held devices
• Touch screen monitors
• Point-of-sales terminals
• Pagers