Datasheet

MCP3911
DS22286A-page 12 © 2012 Microchip Technology Inc.
Note: Unless otherwise indicated, AV
DD
= 3.3V, DV
DD
= 3.3V; T
A
= 25°C, MCLK = 4 MHz; PRESCALE = 1;
OSR = 256; GAIN = 1; Dithering = Maximum; V
IN
= -0.5 dBFS @ 60 Hz, VREFEXT = 0; CLKEXT = 1,
AZ_FREQ = 0; BOOST = 1X.
FIGURE 2-7: Spurious Free Dynamic
Range Histogram.
FIGURE 2-8: SNR Histogram.
FIGURE 2-9: Noise Histogram.
FIGURE 2-10: ENOB SINAD Histogram.
FIGURE 2-11: ENOB SNR Histogram.
FIGURE 2-12: THD vs. OSR.
e
ncy of Occurrence
104.5 106 107.5 109 110.5 112 113.5 115
Frequ
e
Spurious Free Dynamic Range (dBFS)
u
ency of Occurrence
94.5 94.6 94.8 94.9 95.1 95.2 95.4 95.5 95.6 95.8 95.9
Frequ
Signal to Noise Ratio (dB)
1000
1500
2000
2500
3000
3500
4000
4500
5000
u
ency Of Occurrence
Channel 1
V
IN
= 0V
T
A
= 25 C
16384 Consecutive
Readings
0
500
1000
Freq
u
Output Code (LSB)
q
uencyofOccurrence
15.3 15.4 15.4 15.4 15.5 15.5 15.5 15.5 15.6 15.6
Fre
q
EffectiveNumberofBits(SINAD)
q
uencyofOccurrence
15.4 15.4 15.5 15.5 15.5 15.5 15.6 15.6 15.6 15.6
Fre
q
EffectiveNumberofBits(SNR)
-
80
-70
-60
-50
-40
-30
-20
-10
0
m
onic Distortion (dBc)
Di
t
h
e
rin
g
= M
ed
i
u
m
Dithering = Minimum
Dithering = None
-120
-110
-100
-90
80
32 64 128 256 512 1024 2048 4096
Total Har
m
Oversampling Ratio (OSR)
Dithering = Maximum
te g
ed u