38.8 Transfer Function

A typical transfer function of the 12-bit ADC is illustrated in the following figure. The difference of the input voltages (VINH - VINL) is compared with the reference (VREFH - VREFL).
  • The first code transition (A) occurs when the input voltage is (VREFH - VREFL/8192) or 0.5 LSb.
  • The 0000 0000 0001 code is centered at (VREFH - VREFL/4096) or 1.0 LSb (B).
  • The 1000 0000 0000 code is centered at (2048 * (VREFH - VREFL)/4096) (C).
  • An input voltage less than (1 * (VREFH - VREFL)/8192) converts as 0000 0000 0000 (D).
  • An input greater than (8192 * (VREFH - VREFL)/8192) converts as 1111 1111 1111 (E).
Figure 38-11. Analog-to-Digital Transfer Function