afs600 Actel Corporation, afs600 Datasheet - Page 104

• Manufacturer Part Number: afs600
• Description: Actel Fusion Programmable System Chips Mixed-signal Family With Optional Arm Support
• Manufacturer: Actel Corporation

ADC Input Multiplexer
At the input to the Fusion ADC is a 32:1 multiplexer. Of
the 32 input channels, up to 30 are user definable. Two of
these channels are hardwired internally. Channel 31
connects to an internal temperature diode so the
temperature of the Fusion device itself can be monitored.
Channel 0 is wired to the FPGA’s 1.5 V V
the Fusion device to monitor its own power supply. Doing
this internally makes it unnecessary to use an analog I/O to
support these functions. The balance of the MUX inputs
are connected to Analog Quads (see the
section on page
Quad inputs are associated with which specific analog
MUX channels. The number of Analog Quads present is
device-dependent; refer to the family list in
Table 2-39 • Analog MUX Channels
2 -9 0
Analog MUX Channel
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Actel Fusion Programmable System Chips
2-75).
Table 2-39
defines which Analog
CC
supply, enabling
"Analog Quad"
Table 1 on
A d v a n c e d v 1 . 4
Vcc_analog
page i
device. Regardless of the number of quads populated in a
device, the internal connections to both V
internal temperature diode remain on Channels 0 and 31,
respectively. To sample the internal temperature monitor,
it must be strobed (similar to the AT pads). The TMSTBINT
pin on the Analog Block macro is the control for strobing
the internal temperature measurement diode.
To determine which channel is selected for conversion,
there is a five-pin interface on the Analog Block,
CHNUMBER[4:0], defined in
Table 2-39
MUX input channels and the analog input pins.
Signal
AC0
AC1
AC2
AC3
AC4
AC5
AC6
AC7
AV0
AV1
AV2
AV3
AV4
AV5
AV6
AV7
AT0
AT1
AT2
AT3
AT4
AT5
AT6
AT7
of this datasheet for the number of quads per
shows the correlation between the analog
Analog Quad Number
Table 2-40 on page
Analog Quad 0
Analog Quad 1
Analog Quad 2
Analog Quad 3
Analog Quad 4
Analog Quad 5
Analog Quad 6
Analog Quad 7
CC
and the
2-91.