TMS320F2809, TMS320F2808, TMS320F2806
TMS320F2802, TMS320F2801, UCD9501
TMS320C2802, TMS320C2801, and TMS320F2801x DSPs
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SPRS230H–OCTOBER 2003–REVISED JUNE 2006
R
1 kΩ
on
Switch
R
s
ADCIN0
C
10 pF
C
h
1.64 pF
p
Source
Signal
ac
28x DSP
Typical Values of the Input Circuit Components:
Switch Resistance (R ):
1 kΩ
1.64 pF
on
Sampling Capacitor (C ):
h
Parasitic Capacitance (C ): 10 pF
p
Source Resistance (R ):
50 Ω
s
Figure 6-22. ADC Analog Input Impedance Model
6.9.7.2 Definitions
Reference Voltage
The on-chip ADC has a built-in reference, which provides the reference voltages for the ADC.
Analog Inputs
The on-chip ADC consists of 16 analog inputs, which are sampled either one at a time or two channels at
a time. These inputs are software-selectable.
Converter
The on-chip ADC uses a 12-bit four-stage pipeline architecture, which achieves a high sample rate with
low power consumption.
Conversion Modes
The conversion can be performed in two different conversion modes:
•
•
Sequential sampling mode (SMODE = 0)
Simultaneous sampling mode (SMODE = 1)
120
Electrical Specifications
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