Document # 001-20559 Rev. *D
291
27.
Decimator
This chapter explains the PSoC Decimator block and its associated registers. The decimator block is a hardware assist for
digital signal processing applications. The decimator is used for delta-sigma ADCs and incremental ADCs. For a complete
table of the decimator registers, refer to the
“Summary Table of the System Resource Registers” on page 272
. For a quick ref-
erence of all PSoC registers in address order, refer to the
Register Details chapter on page 47
.
27.1
Architectural Description
27.1.1
Decimator Block
The decimator block used by theCY8C24533, CY8C23533,
CY8C23433 CY8C24633 device family performs either a
single or double integration of the discrete-time, discrete-
amplitude signal applied to the data input pin of the block.
The integrated value is up to 16 bits long and read or
cleared by way of a register interface.
Because the data input to the decimator is only one bit, the
input signal's amplitude can only be one of two values:
Because the input signal is a discrete-time signal, the weight
of each encoding is analogous to the area under the signal
for that instant in time. Therefore, to integrate the signal, the
sum of the weights must be calculated over a period of time.
When the decimator is configured as a single integrator, this
is exactly what happens. For each period of the input clock,
the current area (integral value) is either increased by one
(weight = +1, encoding = 1) or decreased by one (weight = -
1, encoding = 0).
The major functional units within the decimator block are
illustrated below.
Figure 27-1. Decimator Architecture
The decimator is divided into two major functional units: a
logic block composed of standard logic cells and a custom
digital data path block. The logic block interfaces to all of the
decimator block pins, except for the data bus. The logic
block takes the decimator's inputs and creates the neces-
sary control input to the custom block. The custom block is
where the adding and storing of accumulated values occurs.
The custom block also interfaces to the data bus.
Table 27-1. Input Signal Amplitude
Encoding
Weight
0
-1
1
+1
Standard
Logic
Control
Inputs
DB[7:0]
Custom
Data Path
8
Data Input
Summary of Contents for PSoC CY8C23533
Page 4: ...Contents Overview 4 Document 001 20559 Rev D Section G Glossary 385 Index 401 ...
Page 16: ...Contents Overview 16 Document 001 20559 Rev D ...
Page 24: ...24 Document 001 20559 Rev D Section A Overview ...
Page 30: ...30 Document 001 20559 Rev D Pin Information ...
Page 54: ...54 Document 001 20559 Rev D Supervisory ROM SROM ...
Page 60: ...60 Document 001 20559 Rev D RAM Paging ...
Page 68: ...68 Document 001 20559 Rev D Interrupt Controller ...
Page 76: ...12 Document 001 20559 Rev D General Purpose IO GPIO ...
Page 82: ...18 Document 001 20559 Rev D Internal Main Oscillator IMO ...
Page 84: ...20 Document 001 20559 Rev D Internal Low Speed Oscillator ILO ...
Page 90: ...26 Document 001 20559 Rev D External Crystal Oscillator ECO ...
Page 94: ...30 Document 001 20559 Rev D Phase Locked Loop PLL ...
Page 106: ...42 Document 001 20559 Rev D Sleep and Watchdog ...
Page 228: ...164 Document 001 20559 Rev D Section D Digital System ...
Page 234: ...170 Document 001 20559 Rev D Array Digital Interconnect ADI ...
Page 278: ...214 Document 001 20559 Rev D Digital Blocks ...
Page 296: ...232 Document 001 20559 Rev D Analog Interface ...
Page 304: ...240 Document 001 20559 Rev D Analog Array ...
Page 308: ...244 Document 001 20559 Rev D Analog Input Configuration ...
Page 312: ...248 Document 001 20559 Rev D Analog Reference ...
Page 338: ...274 Document 001 20559 Rev D Section F System Resources ...
Page 354: ...290 Document 001 20559 Rev D Multiply Accumulate MAC ...
Page 374: ...310 Document 001 20559 Rev D I2C ...
Page 400: ...336 Document 001 20559 Rev D Section G Glossary ...