LTC 2664 - Want +/- 2.5 V output, minimum V+/V-?

Hi,

I understand I need to tie the MSPAN pins in a certain configuration for fixed +/- 2.5 V output from the DAC, but I would like to know what is the minimum differential supply (V+/V-) I need to use if I want to guarantee +/- 2.5 V output, so I don't need to supply the full +/- 15 V if I do not want to use full range of outputs. Can I just supply +/- 5 V to V+/V- to guarantee +/- 2.5 V output? Would IOVcc change as well, or can that be left at 5 V? Where is the information on the datasheet that outlines the relationship between differential supply levels and guaranteed outputs?

The datasheet specifies a range for the differential supply and also specifies it does not need to be symmetrical, however it is not clear what minimum level of supply can guarantee certain outputs that are below +/- 10 V output from the DAC. Any guidance is appreciated, thanks.

Parents
  • 0
    •  Analog Employees 
    on Oct 1, 2018 3:38 PM

    The minimum supply voltages for the LTC2664 are +/-4.6V.  The maximum output swing you can get with a loaded output is V+ -1.4V and V-+1.4V.  So with a +/-5V supply you can use a range that is +/-3.6V  this gives enough headroom to easily use the +/-2.5V range. 

    IOVcc can remain at 5V.  The supplies do not need to be symmetric, just over (or under) that 1.4V margin. 

Reply
  • 0
    •  Analog Employees 
    on Oct 1, 2018 3:38 PM

    The minimum supply voltages for the LTC2664 are +/-4.6V.  The maximum output swing you can get with a loaded output is V+ -1.4V and V-+1.4V.  So with a +/-5V supply you can use a range that is +/-3.6V  this gives enough headroom to easily use the +/-2.5V range. 

    IOVcc can remain at 5V.  The supplies do not need to be symmetric, just over (or under) that 1.4V margin. 

Children