blob: ceceda44a67c231dbe63ae26f6128e12b2a6729b [file] [log] [blame]
P- poly precision resistors
---------------------------
Spice Model Information
~~~~~~~~~~~~~~~~~~~~~~~
- Cell Name: :cell:`res_xhigh_po_XpXX`, :cell:`sky130_fd_pr__res_xhigh_po`
- Model Type: subcircuit
Operating ranges where SPICE models are valid
- :math:`|V_{r0} – V_{r1}| = 0` to 5.0V
- Currents up to 500 µAm of width (preferred use 100 µAm)
Details
~~~~~~~
The resistors have 5 different fixed widths, plus a variable W/L option.
- 0.35 (0p35)
- 0.69 (0p69)
- 1.41 (1p41)
- 2.85 (2p83)
- 5.73 (5p73)
They are modeled as subcircuits, using a conventional resistor model combined with the capacitance under the resistor, as well as matching parameters and temperature coefficients. The fixed-width resistors may only be used in the above configurations. Each resistor end is contacted using a slot licon. Length is variable and measured between the front ends of the slot licons.
The resistors are modeled using the same equations as for the P+ poly resistors. In the case of the P- poly resistors, a separate implant is used to set the sheet resistance to 2000 ohm/sq.
Fixed value resistors have the same layout footprints as their P+ poly counterparts. Electrical and e-test specs are still TBD, once sufficient silicon has been evaluated. More details on the use of the precision resistors, and their models, are in the document ***SKY130 process Family Device Models*** (002-21997), currently under development.
The symbols for the 2000 ohm/sq precision resistors are shown below:
|symbol-res_xhigh_po_0p35| |symbol-res_xhigh_po_0p69|
:model:`sky130_fd_pr__res_xhigh_po_0p35` :model:`sky130_fd_pr__res_xhigh_po_0p69`
|symbol-res_xhigh_po_1p41| |symbol-res_xhigh_po_2p85|
:model:`sky130_fd_pr__res_xhigh_po_1p41` :model:`sky130_fd_pr__res_xhigh_po_2p85`
|symbol-res_xhigh_po_5p73|
:model:`sky130_fd_pr__res_xhigh_po_5p73`
A generic version of the poly resistor is also available, which permits user inputs for W and L, and connections in series or parallel.
|symbol-res_xhigh_po|
.. |symbol-res_xhigh_po_0p35| image:: symbol-res_xhigh_po_0p35.svg
.. |symbol-res_xhigh_po_0p69| image:: symbol-res_xhigh_po_0p69.svg
.. |symbol-res_xhigh_po_1p41| image:: symbol-res_xhigh_po_1p41.svg
.. |symbol-res_xhigh_po_2p85| image:: symbol-res_xhigh_po_2p85.svg
.. |symbol-res_xhigh_po_5p73| image:: symbol-res_xhigh_po_5p73.svg
.. |symbol-res_xhigh_po| image:: symbol-res_xhigh_po.svg