TMS320F2809, TMS320F2808, TMS320F2806
TMS320F2802, TMS320F2801, UCD9501
TMS320C2802, TMS320C2801, and TMS320F2801x DSPs
www.ti.com
SPRS230H–OCTOBER 2003–REVISED JUNE 2006
Figure 4-8 shows the ADC pin-biasing for internal reference and Figure 4-9 shows the ADC pin-biasing for
external reference.
ADCINA[7:0]
ADCINB[7:0]
ADCLO
ADC 16-Channel Analog Inputs
Analog input 0−3 V with respect to ADCLO
Connect to analog ground
ADCREFIN
Float or ground if internal reference is used
22 kW
ADC External Current Bias Resistor ADCRESEXT
(A)
2.2 mF
ADC Reference Positive Output
ADC Reference Medium Output
ADCREFP
ADCREFM
ADCREFP and ADCREFM should not
be loaded by external circuitry
(A)
2.2 mF
V
V
DD1A18
ADC Analog Power Pin (1.8 V)
ADC Analog Power Pin (1.8 V)
DD2A18
ADC Power
V
V
ADC Analog Ground Pin
ADC Analog Ground Pin
SS1AGND
SS2AGND
ADC Analog Power Pin (3.3 V)
ADC Analog Ground Pin
V
V
DDA2
SSA2
ADC Analog and Reference I/O Power
ADC Analog Power Pin (3.3 V)
ADC Analog I/O Ground Pin
V
V
DDAIO
SSAIO
A. TAIYO YUDEN LMK212BJ225MG-T or equivalent
B. External decoupling capacitors are recommended on all power pins.
C. Analog inputs must be driven from an operational amplifier that does not degrade the ADC performance.
Figure 4-8. ADC Pin Connections With Internal Reference
62
Peripherals
TI [ TEXAS INSTRUMENTS ]
