Q1: What is the maximum voltage that the ADG5401F can withstand?
A1: The ADG5401F can withstand voltages up to ±60V on the S and SFB inputs.
Q2: At what threshold will the part detect an Over Voltage signal?
A2 The ADG5401F will detect any voltage > VDD +0.7V or < VSS -0.7V as a Fault and implement the Over Voltage Protection mechanism.
Q3: Is the Over Voltage threshold programmable?
A3: The Over Voltage threshold limit is determined by the supply voltage level. The supply Voltage range is Dual supply range of ± 5V to ±22V or Single Supply range of +8V to +44V. The selected supply value will set the trip threshold for the Over Voltage Protection mechanism to kick in.
Q4: What is the purpose of the secondary feedback channel?
A4: When the ADG5401F is used to protect an amplifier or DAC output the secondary feedback channel is used to close the feedback loop outside of the main switch channel.
Q5: What is the purpose of the internal open loop prevention switch?
A5: When protecting an amplifier output the open loop prevention switch keeps the amplifier output stable by keeping the feedback channel loop in tact when the switch channels are open.
Q6 How do I connect the feedback channel if it is not required?
A6: It is recommended to connect the feedback channel to the main channel even if it is not required. (S->SFB, D->DFB).
Q7: What is the internal Power Condition switch?
A7: The power on condition switch feature is a user configurable switch that pulls the source (S) pin of the switch to ground through a 30kOHm resister when the switch is disabled and no fault is present.
Q8: How quickly will the switch open when a fault occurs?
A8: The datasheet specifies Over Voltage Response Time. There are 2 times specified – tRESPONSE for Positive Fault and tRESPONSE for Negative Fault. These values specify the time from fault detection to when the switch opens.
Q9: Is there any current shunted to the supplies in an Over Voltage scenario?
A9: No, There is no path from the S and SFB pins to the supplies that would shunt current to the supplies during an Over Voltage Fault event. The switch is open during this over voltage and therefore prevents any current flowing through the switch path. The ADG5401F datasheet specifies the Leakage current during an over voltage event and there is a slight increase in the leakage current
Q10: Is the switch guaranteed open when VDD and VSS are not on?
A10: Yes the switch is guaranteed open when VDD and VSS are not applied to the ADG5401F.
Q11:Does the FF pin reset when the fault condition disappears?
A11: The FF pin will reset once the Fault condition is removed. The user does not need to reset the FF flag. The ADG5401F Datasheet specifies Over Voltage Recovery Time tRECOVERY and Interrupt Flag Recovery time tDIGREC these times indicate the time taken by the ADG5401F to recover once the fault is removed and the time for the Fault Flag to reset once the fault is removed respectively.
Q12: Can the Digital signals be applied to the ADG5401F when VDD and VSS are not on?
A12: The Digital Inputs have an absolute maximum rating from GND-0.7V to 6V and is independent of VDD and VSS supplies. Therefore the part can tolerate the digital inputs being applied prior to the supplies being applied to the ADG5401F. However as with any absolute maximum rating the part should not be left in this condition for long periods of time.
Q13: What is the Over current limit on the ADG5401F?
A13: The max continuous current at 25 °C the ADG5401F can pass is 163mA. There is no overcurrent protection on the ADG5401F.
Q14: What is the difference between the ADG5401 and the new ADG5401F devices?
A14: The ADG5401F has +/-60 V Fault protection, Over voltage detection mechanism, Feedback channel for open loop prevention, Fault Flag to indicate when an over voltage condition occurred. Both the ADG5401 and ADG5401F are latch up immune. The ADG5401F has lower logic threshold levels and therefore can work with lower supply voltage digital hosts.