1. Field of the Invention
The present invention relates to an analog-to-digital converter with built-in self test, and more particularly, to an analog-to-digital converter performs a mutual test between capacitor arrays to detect if the capacitor array and related circuitry conform to the desired resolution requirement, and then utilizes the capacitor array, which has been completely tested, to detect if a resistor string conforms to another resolution requirement of the analog-to-digital converter.
2. Description of the Prior Art
Regarding the test of integrated linearity error (INL) of a conventional n-bit successive approximation register analog-to-digital converter (SAR ADC), an additional ramp generator is required for the built-in self test purposes, which increases the chip area greatly. However, if an external analog testing station is alternatively employed, the test cost is increased inevitably and the test is very time-consuming.