Texas Instruments MSP50C6xx - Manual (Page 357)

Application Circuits
6-3 Applications
It is of particular importance to provide a separate decoupling capacitor for the
V
DD
, V
SS
pair which services the DAC. These pins are pad numbers 21 and
19, respectively. The relatively high current demands of the digital-to-analog
circuitry make this a requirement.
An alternate circuit, for better clock-precision and better battery life, includes
a crystal oscillator. See Figure 6–2.
Figure 6–2. Minimum Circuit Configuration for the C614/P614 Using a Crystal-Referenced
Oscillator
5 V
0.1
µ
F
(5)
3300 pF
OSC
IN
OSC
OUT
PLL
DAC
P
DAC
M
V
PP
V
DD
1N914 †
32
Ω
RESET
V
SS
5
5
1
µ
F
(20%)
1 k
Ω †
100 k
Ω
5 V
1N914
Reset
Switch
To pin 2 of Scan Port Connector †
To pin 1 of Scan Port Connector †
(optional )
22 pF
22 pF
32 kHz
10 M
Ω
10 M
Ω
MSP50C614/
MSP50P614
(optional )
(MSP50P614 only)
† The diode across V
DD
and V
PP
may be omitted (shorted), if the application does not require use of the scan port
interface. The same applies for the 1-k
Ω
resistor which appears at the RESET pin; the resistor may be shorted
if not using the scan port. However, the footprint for the resistor is strongly recommended for any MSP50C614
production board. Refer to the Important Note regarding Scan Port Bond Out appearing in Chapter 7.