Datasheet
50
60
70
80
90
100
110
120
0 20 40 60 80 100
TX Dynamic Range (dB)
% of Full-Scale LED Current
75mA & 150mA Range
200mA Range
50mA & 100mA Range
C029
50
60
70
80
90
100
110
120
0 20 40 60 80 100
TX Dynamic Range (dB)
% of Full-Scale LED Current
75mA & 150mA Range
200mA Range
50mA & 100mA Range
C030
10
11
12
13
14
15
0 10 20 30 40 50
Noise-Free Bits in 20Hz Bandwidth
Pleth Current (A)
Duty Cycle 1%
Duty Cycle 5%
Duty Cycle 10%
Duty Cycle 15%
Duty Cycle 20%
Duty Cycle 25%
C027
For each setting RF adjusted for Full-
Scale Output.
Amb Cancellation & stage 2 Gain = 4
used for Low Pleth currents (0.125uA,
0.25uA & 0.5uA).
RMS noise is calculated in 20Hz B/W &
NFB is calculated using 6.6 u RMS noise.
10
11
12
13
14
15
16
0 10 20 30 40 50
Noise-Free Bits in 20Hz Bandwidth
Pleth Current (A)
Duty cycle 1%
Duty cycle 5%
Duty cycle 10%
Duty cycle 15%
Duty cycle 20%
Duty cycle 25%
C028
For each setting RF adjusted for Full-Scale
Output.
Amb Cancellation & stage 2 Gain = 4 used for
Low Pleth currents (0.125uA, 0.25uA &
0.5uA).
RMS noise is calculated in 20Hz B/W & NFB is
calculated using 6.6 u RMS noise.
10
11
12
13
14
15
16
0 10 20 30 40 50
Noise-Free Bits in 20Hz Bandwidth
Pleth Current (A)
Duty Cycle 1%
Duty Cycle 5%
Duty Cycle 10%
Duty Cycle 15%
Duty Cycle 20%
Duty Cycle 25%
C025
For each setting RF adjusted for Full-Scale Output.
Amb Cancellation & stage 2 Gain = 4 used for Low Pleth currents (0.125uA, 0.25uA & 0.5uA).
RMS noise is calculated in 20Hz B/W & NFB is calculated using 6.6 u RMS noise.
10
11
12
13
14
15
16
0 10 20 30 40 50
Noise-Free Bits in 20Hz Bandwidth
Pleth Current (A)
Duty Cycle 1%
Duty Cycle 5%
Duty Cycle 10%
Duty Cycle 15%
Duty Cycle 20%
Duty Cycle 25%
C026
For each setting RF adjusted for Full-Scale Output.
Amb Cancellation & stage 2 Gain = 4 used for Low Pleth currents (0.125uA, 0.25uA & 0.5uA).
RMS noise is calculated in 20Hz B/W & NFB is calculated using 6.6 u RMS noise.
AFE4490
www.ti.com
SBAS602F –DECEMBER 2012–REVISED OCTOBER 2013
TYPICAL CHARACTERISTICS (continued)
At T
A
= +25°C, RX_ANA_SUP = RX_DIG_SUP = 3.0 V, TX_CTRL_SUP = LED_DRV_SUP = 5 V, and f
CLK
= 8 MHz, unless
otherwise noted.
Figure 27. NOISE-FREE BITS vs Figure 28. NOISE-FREE BITS vs
PLETH CURRENT (BW = 20 Hz, PRF = 600 Hz) PLETH CURRENT (BW = 20 Hz, PRF = 1200 Hz)
Figure 29. NOISE-FREE BITS vs Figure 30. NOISE-FREE BITS vs
PLETH CURRENT (BW = 20 Hz, PRF = 2500 Hz) PLETH CURRENT (BW = 20 Hz, PRF = 5000 Hz)
Figure 31. TRANSMITTER DYNAMIC RANGE Figure 32. TRANSMITTER DYNAMIC RANGE
(5-Hz BW) (20-Hz BW)
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