Multi-stage trans-impedance amplifier (tia) for an ultrasound device

Abstract

An ultrasound circuit comprising a multi-stage trans-impedance amplifier (TIA) is described. The TIA is coupled to an ultrasonic transducer to amplify an electrical signal generated by the ultrasonic transducer in response to receiving an ultrasound signal. The TIA may include multiple stages, at least two of which operate with different supply voltages. The TIA may be followed by further processing circuitry configured to filter, amplify, and digitize the signal produced by the TIA.

What is claimed is: 
     
         1 . An ultrasound apparatus, comprising:
 an ultrasonic transducer; and   a multi-stage trans-impedance amplifier (TIA) having an input terminal coupled to the ultrasonic transducer and configured to receive and amplify an analog electrical signal from the ultrasonic transducer, the multi-stage TIA comprising a first stage configured to receive a first supply voltage and a second stage configured to receive a second supply voltage different than the first supply voltage.   
     
     
         2 . The ultrasound apparatus of  claim 1 , wherein the second supply voltage is greater than the first supply voltage. 
     
     
         3 . The ultrasound apparatus of  claim 1 , wherein the ultrasonic transducer and the multi-stage TIA are integrated on a same substrate. 
     
     
         4 . The ultrasound apparatus of  claim 1 , further comprising a switch coupling the multi-stage TIA with the ultrasonic transducer. 
     
     
         5 . The ultrasound apparatus of  claim 1 , further comprising a feedback impedance coupling the second stage with the first stage. 
     
     
         6 . An ultrasound on a chip device, comprising:
 a substrate;   a plurality of ultrasonic transducers integrated on the substrate; and   analog processing circuitry integrated on the substrate and coupled to the plurality of ultrasonic transducers, the analog processing circuitry comprising a multi-stage trans-impedance amplifier coupled to an ultrasonic transducer of the plurality of ultrasonic transducers, the multi-stage TIA comprising multiple stages configured to receive different supply voltages.   
     
     
         7 . The ultrasound on a chip device of  claim 6 , wherein the multiple stages of the multi-stage TIA include an upstream stage and a downstream stage, the upstream stage being configured to operate at a lower supply voltage than the downstream stage. 
     
     
         8 . The ultrasound on a chip device of  claim 6 , wherein the multiple stages of the multi-stage TIA include a first stage and a last stage, the last stage coupled to a larger supply voltage than the first stage. 
     
     
         9 . The ultrasound on a chip device of  claim 6 , further comprising filtering and time gain compensation circuitry coupled to the multi-stage TIA. 
     
     
         10 . The ultrasound on a chip device of  claim 6 , further comprising an averaging circuit having an input coupled to outputs of multiple TIAs of the ultrasound on a chip device. 
     
     
         11 . A method of operating an ultrasound circuit, comprising:
 receiving and amplifying, with a first stage of a multi-stage trans-impedance amplifier, an electrical signal output by a an ultrasonic transducer, the first stage of the multi-stage TIA operating at a first supply voltage value; and   amplifying, with a second stage of the multi-stage TIA operating at a second supply voltage value different than the first supply voltage value, an output signal of the first stage.   
     
     
         12 . The method of  claim 11 , wherein the second supply voltage is greater than the first supply voltage. 
     
     
         13 . The method of  claim 12 , wherein the first supply voltage is less than half the second supply voltage. 
     
     
         14 . The method of  claim 11 , further comprising providing a feedback signal from the second stage to the first stage. 
     
     
         15 . The method of  claim 11 , further filtering and time gain compensating an output signal of the multi-stage TIA.