SmartFinger^® Film Application Specific Integrated Circuit (ASIC)

The SmartFinger^® ASIC is designed for applications where ease of integration combined with excellent image quality and low current consumption is required.

In addition to analog front end amplifiers and analog to digital conversion, the SmartFinger^® ASIC provides a combined serial data and control interface supporting high data rates.

The SmartFinger^® ASIC provides on-chip digital signal processing features for optimized performance and reduced host processor load, together with automatic wake up functionality and various other programmable features for power-saving purposes.

Both data and control is supported by a single SPI enabling a simple interface to a host controller, microprocessor or the dedicated IDEX SmartFinger^® Secure Processor (SSP). The SmartFinger^® ASIC is configured as a slave device for communication speeds up to 48 Mbit/s, depending on I/O supply voltage. The data rate on the SPI interface during transmission of image data can be adjusted within a wide range.

In a typical application, the SmartFinger^® Film ASIC is powered by a low noise3.0 V-3.3 V single supply voltage and requires a 12, 13, 16, 24 or 32 MHz system clock supplied by the host controller. IO supply voltage can be set from 1.8 to 3.3V.  

The line rate of the ASIC, which is programmable, allowing for customizing the transfer rate of fingerprint data to the host processor. Furthermore, programmable scanning frequency allows for optimization of current consumption and adjusting the implementation to the actual application.

The integrated, programmable Wake-Up function enables for reduced current consumption in that the image mode is not activated until the presence of a finger is detected on the surface of the sensor.

Decoupling capacitors can be mounted onto the sensor substrate as an integrated part of the SmartFinger^® Film sensor or externally.