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TS12A4514: High resistance

Daniel Vasher
Intellectual 1135 points
Part Number: TS12A4514

Hello all,

When using the TS12A4514P device we are experiencing a high resistance instead of a low On-State Resistance.

What could be causing this?

  • 0
    TI__Mastermind 45430 points

    Daniel,

    What conditions are you experiencing high resistance?  How high is the resistance?  How are you measuring the resistance? 

    What is the voltage on the supply pin, control, logic, signal path, etc. 

    Do you have scope shots and a schematic you can share? 

    Thank you,

    Adam

  • 0 in reply to Adam Torma
    TI__Intellectual 1135 points
    Hello Adam,
    I will have the customer respond to your reply.
    Thank you.
  • 0 in reply to Adam Torma
    Prodigy 10 points

    Adam,

    Thank you in advance for your contribution to the question. Using a DVM and attaching probes across COM and NO, resistance through the switch is measured. In both the off and on states the resistance is in the hundreds of kilohms. 

    The switch is operated via µC (micro-controller) output and 5VDC supply. The switch is intended to divert the signal path between either a monitoring circuit or µC input. The signal itself is variable and of low potential, mV to just a few volts, which may be problematic for this device. To clarify device operation, does this device need a minimum and steady voltage at the switch terminals (not supply pin) in order to energize and in this case close to pass a signal? 

    Currently there are no screen captures to share. 

    Best,

    Michael

  • 0 in reply to Michael C7
    TI__Mastermind 45430 points

    Michael,

    The TS12A4514 should be low impedance when Vcc = 12 V and IN = 5V.  Something isn't happening correctly if you are seeing kilo ohms when the IN pin is both 0V and 5V.

    What is the voltage on the supply pin?  You say the voltage on the IN pin is 5V correct?   Are you able to increase the IN pin voltage or reduce the Vcc voltage?  It might be possible the FET switch is not turning on because the Vih logic threshold is not being crossed to turn on the device. 

    This is a passive FET switch that you can imagine the source being COM and drain being NO.  The gate of the FET is biased by Vcc and the control logic pin IN pin. There is no minimum voltage needed on the COM or NO pin to activate this device.  The voltages needed to turn on the FET is VCC and IN. 

    Adam   

  • 0 in reply to Adam Torma
    TI__Mastermind 45430 points
    Micheal,

    Do you have any update on the testing?

    Thank you,
    Adam
  • 0 in reply to Adam Torma
    TI__Mastermind 45430 points
    Michael,

    I'm closing this thread due to inactivity. If you need additional support replying here will reopen the thread. You may also create a new thread.

    Thank you,
    Adam