Analog-to-Digital Converter (ADC)
MCF52110 ColdFire® Integrated Microcontroller Reference Manual, Rev. 1
25-24
Freescale Semiconductor
Preliminary
Figure 25-20. Input Select Mux
Parallel, Single Ended
The two 1-of-4 select muxes can be
set for the appropriate input line.
The lower switch selects V
REFL
for the
V- input of the A/D. The upper switch is
always closed so that any of the four
inputs can get to the V+ A/D input.
Parallel, Differential
The channel select switches are
turned on in pairs, providing a dual
1-of-2 select function, such that either
of the two differential channels can be
routed to the A/D input.
The upper and lower switches are
open and the middle switch is closed,
providing the differential channel to
the differential input of the A/D.
Table 25-20. Analog MUX Controls for Each Conversion Mode (continued)
Conversion Mode
Channel Select Switches
Single Ended Differential Switches
AN3
AN2
AN1
AN0
V
REFL
V+
V–
Channel
Select
To
Converter A
Single-Ended
Interface
Function
MUX Configuration for Differential
vs
Channel Select
Single-Ended vs
Differential
AN7
AN6
AN5
AN4
V
REFL
V+
V–
Channel
Select
To
Converter B
Single-Ended
Interface
Function
AN3
AN2
AN1
AN0
V
REFL
V+
V–
Channel
Select
To
Converter A
Differential
Interface
Function
AN7
AN6
AN5
AN4
V
REFL
V+
V–
Channel
Select
To
Converter B
Differential
Interface
Function
Channel Select
Single-Ended vs
Differential
Channel Select
Single-Ended vs
Differential
Channel Select
Single-Ended vs
Differential
MUX Configuration for Single-Ended
