Games / Command flash cards / Standard-cell library

Standard-cell library checked against the open libraries

Choose a section to drill, or play every section mixed together. Each section lists the commands it covers, and any kinds of card it holds besides the plain one: a command whose meaning you pick.

SourceThese cards describe standard-cell libraries in general, checked against the open libraries that OpenROAD-flow-scripts ships: Nangate45, sky130 high density, and ASAP7. Cell names and conventions differ between libraries, so each card says which library its example comes from. The answers link to the OpenROAD module that handles the cell in question. Reference: OpenROAD module documentation (the open libraries on GitHub).

All sections

A mixed round drawn from every section. Due cards come first, then new cards in random order.

58cards across 7 sections
mixed round play

Naming and drive strength

Reading a cell name: function, drive strength, threshold flavour, and library variant.

INV_X1sky130_fd_sc_hd__inv_1BUFx2_ASAP7_75t_RASAP7_USE_VTsky130hdsky130hs
8 cards play

Combinational cells

Why inverting gates are the cheap ones, and what the compound gates compute.

NAND2_X1AND2_X1AOI21_X1OAI21_X1XOR2_X1MUX2_X1HA_X1FA_X1BUF_X1
9 cards play

Sequential cells

Flip-flop variants, scan flops, latches, and clock gating cells.

DFF_X1DFFR_X1DFFS_X1DFFRS_X1SDFF_X1dlxtp_1CLKGATE_X1CLKGATETST_X1
8 cards play

Clock cells

The cells built for the clock network, and why they are separate.

CLKBUF_X1clkinv_1clkinvlp_2dlygate4sd1_1CTS_LIB_NAME
5 cards play

Physical-only cells

Cells with no logic function: taps, endcaps, fillers, decap, diodes, and ties.

TAPCELL_X1FILLCELL_X1decap_8ANTENNA_X1diode_2LOGIC0_X1LOGIC1_X1conb_1
name the commandput in order
14 cards play

Using the library

The choices a flow makes among the cells, and when each one helps.

threshold voltageupsizingbufferinglogical effortdont-use
4 cards play

Views and characterization

What each library view carries, what a corner is, and the limits a cell declares.

libertylefgdsmax_transitionmax_capacitanceoperating_conditions
10 cards play