LT1236 NC pin

Hi

According to LT1236 datasheet, NC pin is connected internally. Where NC pin is connected internally ? How much the resistance is between NC and GND ? The customer measured it. One is 1.82kohm another one is only 1.57ohm. What's happened the IC ?

As additional info, there is a capacitor between NC and GND on the pcb because they used MAX6250 on their old version pcb instead of LT1236. Does the capacitor cause any problem ?

Regards,

Hiroyuki



write additional info.
[edited by: Hiroyuki.D at 1:46 AM (GMT 0) on 13 May 2019]
Parents
  • 0
    •  Analog Employees 
    on May 15, 2019 3:23 PM

    Hi Hiroyuki-san,

     

    After reviewing LT1236 schematic, these NC pins are internally connected and are used for factory trimming. This means, resistance measurement can vary within NC pins and from part to part.

    Capacitance connected to NC pin can affect the trim precision. Therefore, NC pin should be left floating/no connect.

     

    Regards,

    Anshul 

Reply
  • 0
    •  Analog Employees 
    on May 15, 2019 3:23 PM

    Hi Hiroyuki-san,

     

    After reviewing LT1236 schematic, these NC pins are internally connected and are used for factory trimming. This means, resistance measurement can vary within NC pins and from part to part.

    Capacitance connected to NC pin can affect the trim precision. Therefore, NC pin should be left floating/no connect.

     

    Regards,

    Anshul 

Children