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Enhanced Queued Analog-to-Digital Converter (EQADC)
MPC5644A Microcontroller Reference Manual, Rev. 6
1152
Freescale Semiconductor
25.6.11.1.2
RSD overview
Figure 25-92. RSD Stage Block Diagram
On each pass through the RSD stage, the input signal will be multiplied by exactly two, and summed with
either -VREF, 0, or VREF, depending on the Logic Control. The Logic Control will determine -VREF, 0,
or VREF depending on the two comparator inputs. As the Logic Control sets the summing operation, it
also sends a digital value to the RSD adder. Each time an analog signal passes through the RSD
single-stage, a digital value is collected by the RSD adder. At the end of an entire AD conversion cycle,
the RSD adder uses these collected values to calculate the 12-bit/10-bit/8-bit digital output.
shows the transfer function for the RSD stage. Note how the digital value (a, b) is dependent
on the two comparator inputs.
x2
Sum
VRL
VRH
Input
Voltage
Logic
Control
Residue Voltage
+
-
+
-
-VREF,0,VREF
Digital
Signal
RSD
Adder
Summary of Contents for MPC5644A
Page 2: ...MPC5644A Microcontroller Reference Manual Rev 6 2 Freescale Semiconductor...
Page 24: ...MPC5644A Microcontroller Reference Manual Rev 6 24 Freescale Semiconductor...
Page 26: ...MPC5644A Microcontroller Reference Manual Rev 6 26 Freescale Semiconductor...
Page 52: ...Introduction MPC5644A Microcontroller Reference Manual Rev 6 52 Freescale Semiconductor...
Page 56: ...Memory Map MPC5644A Microcontroller Reference Manual Rev 6 56 Freescale Semiconductor...
Page 1228: ...Decimation Filter MPC5644A Microcontroller Reference Manual Rev 6 1228 Freescale Semiconductor...
Page 1440: ...FlexCAN Module MPC5644A Microcontroller Reference Manual Rev 6 1440 Freescale Semiconductor...