offset voltage problem with analog switch ADG333A, pin-compatible substitute?

Question

Hello, 
 I've got offset voltages of 0,2V with a device containing ADG333ABNZ. Do the pin compatible newer versions like ADG1434 or ADG5434 correct this? 
 Best regards, 
 Simon Brem

ADIApproved · Accepted Answer

Hi DLR, 
 Offsets usually appear when the analog switches are used in high impedance environments (Mohms) and it is mainly caused by leakage currents or charge injection. 
 While leakage is always present and may cause static offsets ( the switch is not toggled, just kept into one position on or off) charge injection may cause dynamic offsets( when the switch is constantly toggled) by dumping charge on the parasitic capacitance of the switch pin plus any additional capacitance of the PCB and external circuitry. The direct effect of the charge injection is voltage spikes on the switch pins, but if they are averaged out it may lead to offsets. 
 You need to establish the nature of the offset in your circuit and maybe choose a different switch. 
 I would recommend trying the ADG1234 which is a low leakage, low charge injection device. If the circuit operates in high impedance environments (Mohms), the ON resistance doesn't really matter as it will always be much lower in comparison with the system impedance. 
 Regards, 
 FEB)

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offset voltage problem with analog switch ADG333A, pin-compatible substitute?