thanh said:
Hi WorkHorse ! Why ? Thanks
Hi Thanh
A cascode-connected
input circuit provides superior performance to the more common differential amplifier in the following areas:
• Better high-frequency response
• Increased high-frequency input impedance (the cascode connection eliminates the input transistor
Miller effect caused by the collector-to-base capacitance (Cob)]
• Superior power-supply noise rejection along with greater CMRR.
Because of their high output impedance, cascode-connected input differential amplifiers are
excellent voltage-to-current converters. If the circuit topology takes full advantage of the differential
input stage, the amplifier power-supply rejection ratio can easily exceed 120 dB.
regards,
K a n w a r