Functional Description; Cmp Functional Modes - NXP Semiconductors freescale KV4 Series Reference Manual

Functional description

Field
MSEL Minus Input Mux Control
Determines which input is selected for the minus input of the comparator. For INx inputs, see CMP, DAC,
and ANMUX block diagrams.
NOTE: When an inappropriate operation selects the same input for both muxes, the comparator
automatically shuts down to prevent itself from becoming a noise generator.
000 IN0
001 IN1
010 IN2
011 IN3
100 IN4
101 IN5
110 IN6
111 IN7
35.4 Functional description
The CMP module can be used to compare two analog input voltages applied to INP and
INM.
CMPO is high when the non-inverting input is greater than the inverting input, and is low
when the non-inverting input is less than the inverting input. This signal can be
selectively inverted by setting CR1[INV] = 1.
SCR[IER] and SCR[IEF] are used to select the condition which will cause the CMP
module to assert an interrupt to the processor. SCR[CFF] is set on a falling-edge and
SCR[CFR] is set on rising-edge of the comparator output. The optionally filtered CMPO
can be read directly through SCR[COUT].

35.4.1 CMP functional modes

There are the following main sub-blocks to the CMP module:
• The comparator itself
• The window function
• The filter function
736
CMPx_MUXCR field descriptions (continued)
KV4x Reference Manual, Rev. 2, 02/2015
Preliminary
Description
Freescale Semiconductor, Inc.