This analog-to-digital converter uses Successive Approximation Register (SAR) architecture to achieve 12-bit resolution. The IP includes a core internal SAR ADC, 8-1 MUX and touch screen drivers. The internal SAR ADC includes sample/hold circuits, a capacitive DAC, a comparator and logic control circuits.
External reference or internal reference is needed. In addition, the reference voltage input will be adjusted to allow encoding smaller analog voltage spanning to the full 12 bits of resolution.
The ADC has dual speed modes – 1M or 200K- working in 200K mode could save some power. Moreover, it supports two running modes: free running and single running. In single running mode, SAR will switch to power down mode automatically so as to save power.
The ADC is especially suitable to act as Touch Screen Controller, demanding less off-chip components to complete the design.
Battery voltage detection could be easily accomplished by the SAR ADC. It has in-chip resistor divider and keypad interrupt signal generator.
The converter has flexible control logic, and could be easily embedded in a complex system.
It is also suitable for integrated auxiliary codec applications and multi-converter architectures in wireless or battery-operated products.
Process: GLOBALFOUNDRIES 0.13μm logic process 1Poly 8Metal, also supports 1P6M, 1P7M and 1P8M
Resolution: 12-bit resolution
DNL: +/-1.5 LSB, INL: +/-3 LSB
Dual Data Rates: 1MSPS/200KSPS
Analog Input Range: VREF to AGND, could be rail-to-rail
Analog Supply: 2.97-3.63V; Digital Supply: 1.2V
8 Single-Ended Analog Inputs
4-wire Touch Screen Interface
Touch Pressure Measurement
Direct Battery Measurement
Keypad Interrupt Generator
Auto Power Down
Low Power Consumption: 4850μW(@1MSPS) / 2170μW(@200KSPS), < 1μA (Auto power down mode)
Flexible Control Logic: can be easily embedded in a system, or operates in “stand alone" mode.
Oct 14, 2011