TC1796
Peripheral Units (Vol. 2 of 2)
Analog-to-Digital Converter (ADC)
User’s Manual
25-1
V2.0, 2007-07
ADC, V2.0
25
Analog-to-Digital Converter (ADC)
The TC1796 contains two medium-speed Analog-to-Digital Converters (ADC0 and
ADC1) with identical functionality and a third fast Analog-to-Digital Converter (FADC).
ADC0 and ADC1 provide 2-3
µ
s conversion time @ 10-bit resolution and are intended
primarily for single-ended signals. They offer a very flexible and comprehensive control
for monitoring a large number of relatively slow signals, including synchronous
conversion of both ADCs.
The FADC offers very fast conversion rates (280 ns @ 10-bit resolution) thus allowing
sampling of high-frequency signals. For slow and mid-range frequency signal heavy
oversampling can be performed to avoid the use of expensive filters.
The FADC is described in
. This chapter describes in detail the two Analog-
to-Digital converters ADC0 and ADC1. It contains the following sections:
•
Functional description of the ADC Kernel for ADC0 and ADC1 (see
•
Register descriptions for all ADC Kernel specific registers (see
)
•
TC1796 implementation-specific details and registers of the ADC0/ADC1 modules,
including port connections and control, service request control, address decoding,
and clock control (see
).
Note: The ADC Kernel register names described in
are referenced in the
TC1796 User’s Manual with the module name prefix “ADC0_” for the ADC0
interface and “ADC1_” for the ADC1 interface.
25.1
ADC Kernel Description
The two on-chip ADC modules of the TC1796 are analog-to-digital converters with 8-bit,
10-bit, or 12-bit resolution including sample & hold functionality. The A/D converters
operate by the method of successive approximation. A multiplexer selects up to
32 analog inputs that can be connected to the 16 conversion channels in each ADC
module. An automatic self-calibration adjusts the ADC modules to changing
temperatures or process variations.
Features
•
8-bit, 10-bit, 12-bit A/D conversion
•
Conversion time below 2.5
µ
s @ 10-bit resolution
•
Extended channel status information on request source
•
Successive approximation conversion method
•
Total Unadjusted Error (TUE) of
±
2 LSB @ 10-bit resolution
•
Integrated sample & hold functionality
•
Direct control of up to 16(32) analog input channels per ADC
•
Dedicated control and status registers for each analog channel
•
Powerful conversion request sources
•
Selectable reference voltages for each channel