Abstract: A circuit, including: a photodetector including a first readout terminal and a second readout terminal different than the first readout terminal; a first readout circuit coupled with the first readout terminal and configured to output a first readout voltage; a second readout circuit coupled with the second readout terminal and configured to output a second readout voltage; and a common-mode analog-to-digital converter (ADC) including: a first input terminal coupled with a first voltage source; a second input terminal coupled with a common-mode generator, the common-mode generator configured to receive the first readout voltage and the second readout voltage, and to generate a common-mode voltage between the first and second readout voltages; and a first output terminal configured to output a first output signal corresponding to a magnitude of a current generated by the photodetector.

Abstract: A method and a device implementing the method for making coffee are provided herein. The method and the related device use pressurized air as a media for pushing water under uniform pressure to flow through the coffee cake such that high-quality crema will be formed. The method basically contains the following steps. First, a water tank partially filled with hot water is provided. Then, high pressure air is filled and maintained within the water tank without releasing. A check valve leading to the coffee cake is then opened and the hot water is pushed by the high-pressure air to flow through the check valve and coffee cake. The temperature of the hot water is between 80˜100° C., and the amount of water is between one to two thirds of the volume of the water tank. The pressure level of the high-pressure air is between 6˜10 atm.