A microphone assembly comprising: an electro-acoustic transducer; an application specific integrated circuit (ASIC) coupled to the electro-acoustic transducer, the ASIC comprising: an oscillator configured to generate an internal clock signal; a one-time programmable memory configured to store first trimming values to compensate the internal clock signal for temperature variations and manufacturing process variations, and second trimming values to further compensate the compensated internal clock signal for variations in manufacturing tolerances of the oscillator; a clock divider configured to receive the compensated internal clock signal and apply a division ratio to the compensated internal clock signal, wherein the division ratio is adjusted by the second trimming values to output a further compensated internal clock signal; at least one operational block; a frequency detection block (114; 300) configured to: receive, from a device external to the microphone assembly, an input clock signal; and compare the input clock signal to the further compensated internal clock signal to determine a frequency of the input clock signal, the frequency indicative of one of a plurality of operational modes (202, 204, 206, 208) of the ASIC; and a bias current generator configured to: determine an amount of current to be provided to the at least one operational block based on the frequency of the input clock signal; and provide the determined amount of current to the at least one operational block to operate the microphone assembly according to an associated operational mode (202, 204, 206, 208), wherein each operational mode has a different current consumption. an electro-acoustic transducer; an application specific integrated circuit (ASIC) coupled to the electro-acoustic transducer, the ASIC comprising: an oscillator configured to generate an internal clock signal; a one-time programmable memory configured to store first trimming values to compensate the internal clock signal for temperature variations and manufacturing process variations, and second trimming values to further compensate the compensated internal clock signal for variations in manufacturing tolerances of the oscillator; a clock divider configured to receive the compensated internal clock signal and apply a division ratio to the compensated internal clock signal, wherein the division ratio is adjusted by the second trimming values to output a further compensated internal clock signal; at least one operational block; a frequency detection block (114; 300) configured to: receive, from a device external to the microphone assembly, an input clock signal; and compare the input clock signal to the further compensated internal clock signal to determine a frequency of the input clock signal, the frequency indicative of one of a plurality of operational modes (202, 204, 206, 208) of the ASIC; and a bias current generator configured to: determine an amount of current to be provided to the at least one operational block based on the frequency of the input clock signal; and provide the determined amount of current to the at least one operational block to operate the microphone assembly according to an associated operational mode (202, 204, 206, 208), wherein each operational mode has a different current consumption. an oscillator configured to generate an internal clock signal; a one-time programmable memory configured to store first trimming values to compensate the internal clock signal for temperature variations and manufacturing process variations, and second trimming values to further compensate the compensated internal clock signal for variations in manufacturing tolerances of the oscillator; a clock divider configured to receive the compensated internal clock signal and apply a division ratio to the compensated internal clock signal, wherein the division ratio is adjusted by the second trimming values to output a further compensated internal clock signal; at least one operational block; a frequency detection block (114; 300) configured to: receive, from a device external to the microphone assembly, an input clock signal; and compare the input clock signal to the further compensated internal clock signal to determine a frequency of the input clock signal, the frequency indicative of one of a plurality of operational modes (202, 204, 206, 208) of the ASIC; and receive, from a device external to the microphone assembly, an input clock signal; and compare the input clock signal to the further compensated internal clock signal to determine a frequency of the input clock signal, the frequency indicative of one of a plurality of operational modes (202, 204, 206, 208) of the ASIC; and a bias current generator configured to: determine an amount of current to be provided to the at least one operational block based on the frequency of the input clock signal; and provide the determined amount of current to the at least one operational block to operate the microphone assembly according to an associated operational mode (202, 204, 206, 208), wherein each operational mode determine an amount of current to be provided to the at least one operational block based on the frequency of the input clock signal; and provide the determined amount of current to the at least one operational block to operate the microphone assembly according to an associated operational mode (202, 204, 206, 208), wherein each operational mode has a different current consumption.