JAJSGJ3E November 2018 – August 2023 DAC60501 , DAC70501 , DAC80501
PRODUCTION DATA
During the sample-to-hold transition, a small amount of charge is injected onto the hold capacitor, mostly because of the stray capacitance of the switch that creates small level changes when transitioning between states. The resulting dc offset is typically referred to as pedestal error. This error contributes to the offset error of the system. The pedestal error, ΔVOUT, is the measured offset voltage resulting from charge injection when the switch transitions to hold state. ΔVOUT is related to charge injection through Equation 2.
where
In most solid-state switch data sheets, charge injection is graphed with respect to supply voltage, analog input, or temperature. A charge injection value of 3 pC is typical in many solid-state switches under the conditions: 25°C, 5-V supply, and 0-V analog input.