Charge Amplifiers that can be implemented in Thin Film and are useful for imaging systems such as Digital Breast Tomosynthesis with Reduced X-Ray Exposure

An apparatus, comprising:

• a circuit comprising:
• a p-i-n diode having a cathode of the p-i-n diode coupled to a cathode bias voltage or ground;
• a charge transistor having a first source/drain terminal coupled to an anode of the p-i-n diode;
• a storage capacitor having a first terminal coupled to a second source/drain terminal of the charge transistor and a second terminal coupled to the cathode of the p-i-n diode;
• an amplification transistor having a gate terminal coupled to the first terminal of the storage capacitor and a first source/drain terminal coupled to a reference voltage in operation;
• a read transistor having a first source/drain terminal coupled to a second source/drain terminal of the amplification transistor;
• a data line having a first terminal coupled to a second source/drain terminal of the read transistor;
• and
• a readout circuit coupled to a second terminal of the data line and configured to provide in operation an output voltage corresponding to charge on the storage capacitor caused by interaction between the p-i-n diode and light.