Datasheet

© 2008 Microchip Technology Inc. DS21298E-page 11
MCP3204/3208
Note: Unless otherwise indicated, V
DD
= V
REF
= 5V, V
SS
= 0V, f
SAMPLE
= 100 ksps, f
CLK
= 20* f
SAMPLE
, T
A
= +25°C.
FIGURE 2-25: Effective Number of Bits
(ENOB) vs. V
REF
.
FIGURE 2-26: Spurious Free Dynamic
Range (SFDR) vs. Input Frequency.
FIGURE 2-27: Frequency Spectrum of
10 kHz input (Representative Part).
FIGURE 2-28: Effective Number of Bits
(ENOB) vs. Input Frequency.
FIGURE 2-29: Power Supply Rejection
(PSR) vs. Ripple Frequency.
FIGURE 2-30: Frequency Spectrum of
1 kHz input (Representative Part, V
DD
= 2.7V).
9.00
9.25
9.50
9.75
10.00
10.25
10.50
10.75
11.00
11.25
11.50
11.75
12.00
0.00.51.01.52.02.53.03.54.04.55.0
V
REF
(V)
ENOB (rms)
V
DD
= V
REF
= 2.7 V
F
SAMPLE
= 50 ksps
V
DD
= V
REF
= 5 V
F
SAMPLE
=100 ksps
0
10
20
30
40
50
60
70
80
90
100
110100
Input Frequency (kHz)
SFDR (dB)
V
DD
= V
REF
= 5 V
F
SAMPLE
= 100 ksps
V
DD
= V
REF
= 2.7 V
F
SAMPLE
= 50 ksps
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
0 10000 20000 30000 40000 50000
Frequency (Hz)
Amplitude (dB)
V
DD
= V
REF
= 5 V
F
SAMPLE
= 100 ksps
F
INPUT
= 9.985 kHz
4096 points
8.0
8.5
9.0
9.5
10.0
10.5
11.0
11.5
12.0
110100
Input Frequency (kHz)
ENOB (rms)
V
DD
= V
REF
= 2.7 V
F
SAMPLE
= 50 ksps
V
DD
= V
REF
= 5 V
F
SAMPLE
= 100 ksps
-80
-70
-60
-50
-40
-30
-20
-10
0
1 10 100 1000 10000
Ripple Frequency (kHz)
Power Supply Rejection (dB)
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
0 5000 10000 15000 20000 25000
Frequency (Hz)
Amplitude (dB)
V
DD
= V
REF
= 2.7 V
F
SAMPLE
= 50 ksps
F
INPUT
= 998.76 Hz
4096 points