Texas Instruments MSC1211EVM, User Manual

Page: 25 / 35

I/O Connectors and Signals
3-9
Operation
3.3.4 J4: Analog Inputs
Terminal block J4 is the main analog input to the MSC1211EVM, as is defined
in Table 3−8. One terminal is provided for each of the nine MSC1211 differen-
tial inputs. Each terminal is connected to the MSC1211 through a 1k
Ω
resistor.
Table 3−8. J4: Analog Inputs
Terminal
Number
Terminal
Name
MSC1211
Pin Number
Function
1 AN0 18 Analog Input 0
2 AN1 19 Analog Input 1
3 AN2 20 Analog Input 2
4 AN3 21 Analog Input 3
5 AN4 22 Analog Input 4
6 AN5 23 Analog Input 5
7 AN6/EXTD 24 Analog Input 6 and
Digital Low Voltage Detect
8 AN7/EXTA 25 Analog Input 7 and
Analog Low Voltage Detect
9 AINCOM 26 Analog Common
10 AGND 17, 27 Analog Ground
3.3.5 J7: External Reference Input
The MSC1211EVM has an onboard 2.5V/1.25V bandgap reference. If a lower-
noise reference source or a reference with a different voltage is desired, it can
be connected to square pin connector J7. The reference source (onboard or
external) is selected using pins 1 and 2 of J7. Bypassing for the reference in-
puts is provided by C17 and C18. To use the internal REFOUT signal, connect
pins 1 and 2 together.
Table 3−9. J7: External Reference Input
Terminal
Number
Function
1 AGND—Analog Ground
2 REF IN−
3 VDAC1/(REF+ for MSC1211)
4 REF IN+/REFOUT
5 Open
6 AV
DD