
CY8CTST120
Document Number: 001-46932 Rev. *B
Page 3 of 32
The Analog System
The Analog System is composed of 6 configurable blocks, each
comprised of an opamp circuit allowing the creation of complex
analog signal flows. Analog peripherals are very flexible and can
be customized to support specific application requirements.
Some of the more common PSoC analog functions (most
available as user modules) are listed below.
■ Analog-to-digital converters (up to 2, with 6 to 14-bit resolu-
tion, selectable as Incremental, Delta Sigma, and SAR)
■ Filters (2 and 4 pole band-pass, low-pass, and notch)
■ Amplifiers (up to 2, with selectable gain to 48x)
■ Instrumentation amplifiers (1 with selectable gain to 93x)
■ Comparators (up to 2, with 16 selectable thresholds)
■ DACs (up to 2, with 6- to 9-bit resolution)
■ Multiplying DACs (up to 2, with 6- to 9-bit resolution)
■ High current output drivers (two with 30 mA drive as a PSoC
Core Resource)
■ 1.3V reference (as a System Resource)
■ Modulators
■ Correlators
■ Peak Detectors
■ Many other topologies possible
Analog blocks are arranged in a column of three, which includes
one CT (Continuous Time) and two SC (Switched Capacitor)
blocks, as shown in Figure 2.
The Analog Multiplexer System
The Analog Mux Bus connects to every GPIO pin in ports 0-5.
Pins are connected to the bus individually or in any combination.
The bus also connects to the analog system for capacitive
sensing with the TrueTouch block comparator. It can be split into
two sections for simultaneous dual-channel processing. An
additional 8:1 analog input multiplexer provides a second path to
bring Port 0 pins to the analog array.
Switch control logic enables selected pins to switch dynamically
under hardware control. This enables capacitive measurement
for the touchscreen application. Other multiplexer applications
include:
■ Chip-wide mux that allows analog input from up to 48 IO pins.
■ Electrical connection between any IO pin combinations.
Figure 2. Analog System Block Diagram
Additional System Resources
System Resources, provide additional capability useful to
complete systems. Additional resources include a multiplier,
decimator, low voltage detection, and power on reset. Brief state-
ments describing the merits of each resource follow.
■ Full-Speed USB (12 Mbps) with five configurable endpoints and
256 bytes of RAM. No external components required except
two series resistors. Wider than commercial temperature USB
operation (-10°C to +85°C).
■ Digital clock dividers provide three customizable clock
frequencies for use in applications. The clocks can be routed
to both the digital and analog systems. Additional clocks can
be generated using digital PSoC blocks as clock dividers.
ACB00
ACB01
Block
Array
Array Input
Configuration
ACI1[1:0]
ASD20
ACI0[1:0]
P0[6]
P0[4]
P0[2]
P0[0]
P2[2]
P2[0]
P2[6]
P2[4]
P0[7]
P0[5]
P0[3]
P0[1]
P2[3]
P2[1]
Reference
Generators
AGNDIn
RefIn
Bandgap
RefHi
RefLo
AGND
ASD11
ASC21
ASC10
Interface to
Digital System
M8C Interface (Address Bus, Data Bus, Etc.)
AnalogReference
All IO
(Except Port 7)
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