Datasheet

ADuC841/ADuC842/ADuC843
Rev. 0 | Page 15 of 88
EXTERNAL REFERENCE (V)
50
0.5
SNR (dBs)
1.0 2.0 2.5 5.0
55
1.5
60
65
70
75
80
THD (dBs)
–100
–95
–90
–85
–80
–75
–70
AV
DD
/DV
DD
= 5V
f
S
= 152kHz
SNR
THD
03260-0-017
Figure 19. Typical Dynamic Performance vs. V
REF
, V
DD
= 5 V
EXTERNAL REFERENCE (V)
SNR (dBs)
80
75
65
50
70
55
AV
DD
/DV
DD
= 3V
f
S
= 152kHz
0.5 1.5 2.5
THD (dBs)
SNR
THD
60
–70
–75
–85
–100
–80
–95
–90
1.0 2.0 3.0
03260-0-018
Figure 20. Typical Dynamic Performance vs. V
REF
, V
DD
= 3 V
FREQUENCY (kHz)
64
92.262
SNR
(dBs)
119.050 172.620 199.410 226.190
66
145.830
68
70
72
76
80
78
74
62
60
65.476
03260-0-019
300.000 350.000 400.000
AV
DD
/DV
DD
= 5V
Figure 21. Typical Dynamic Performance vs. Sampling Frequency
TEMPERATURE ( ° C)
03260-0-100
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
–40 25 85
VOLTAGE
AV
DD
/DV
DD
= 3V
SLOPE = –1.4mV/ ° C
Figure 22. Typical Temperature Sensor Output vs. Temperature
GENERAL DESCRIPTION (continued)
The parts also incorporate additional analog functionality with
two 12-bit DACs, power supply monitor, and a band gap
reference. On-chip digital peripherals include two 16-bit
∑-∆.
DACs, a dual output 16-bit PWM, a watchdog timer, a time
interval counter, three timers/counters, and three serial I/O
ports (SPI, I
2
C, and UART).
On the ADuC812 and the ADuC832, the I
2
C and SPI interfaces
share some of the same pins. For backwards compatibility, this
is also the case for the ADuC841/ADuC842/ADuC843.
However, there is also the option to allow SPI operate separately
on P3.3, P3.4, and P3.5, while I
2
C uses the standard pins. The
I
2
C interface has also been enhanced to offer repeated start,
general call, and quad addressing.
On-chip factory firmware supports in-circuit serial download
and debug modes (via UART) as well as single-pin emulation
mode via the
EA
pin. A functional block diagram of the parts is
shown on the first page.