Datasheet
MC33411A/B
21
MOTOROLA RF/IF DEVICE DATA
0
–60 –50 –40 –30 –20 –10 0 10
–5.0
–10
–15
–20
–25
–30
–35
–40
4.0
3.0
2.0
1.0
0
DISTORTION (%)
Tx OUT VOLTAGE (dBV)
MCI VOLTAGE (dBV)MCI VOLTAGE (dBV)
Figure 21. Tx Output Audio Response
(Lim off, R6/11 = 1)
Figure 22. Tx Output Audio Response
(Lim off, R6/12 = 1)
V
CC
= 3.6 V
T
A
= 25°C
V
CC
= 3.6 V
T
A
= 25°C
Distortion
Tx Out
Tx OUT VOLTAGE (dBV)
0
–60 –50 –40 –30 –20 –10 0 10
–5.0
–10
–15
–20
–25
–30
–35
–40
4.0
3.0
2.0
1.0
0
DISTORTION (%)
Distortion
Tx Out
Data Slicer
The data slicer will receive the low level digital signal from
the RF receiver section at Pin 39. The input signal to the data
slicer must be >200 mVpp. Hysteresis of 40 mV is internally
provided. The output of the data slicer will be same
waveform, but with an amplitude of 0 to V
CC
, and can be
observed at Pin 17 if bits 5/9–8 are set to 00. The output can
be inverted by setting bit 5/9 = 1. The data slicer can be
disabled by setting bit 5/8 = 1.
Receive Audio Path
The Receive Audio Path (Pins 38, 36–33) consists of an
anti–aliasing filter, a low–pass filter, side tone attenuator, gain
adjust stage, a mute switch, expander and volume control.
The switched capacitor low–pass filter is an 8 pole filter,
with a corner frequency at 3.8 kHz. This is designed to
provide bandwidth limiting in the audio range.
The gain stage provides 20 dB of gain adjustment in
1.0 dB steps, measured from Pin 38 to 36. Bits 7/4–0 are
used to set the gain according to Table 3. The mute switch,
controlled by bit 6/1, will mute a minimum of 60 dB.
When the compressor output is within 3.0 dB of the
expander input level, the Rx output (Pin 36) can be attenuated
(referenced to the expander output) by bits 6/10–9. For
6/10–9 = 00, the attenuation is 0 dB. For the other
combinations, 6/10–9 = 01, attenuation = 3.0 dB; 6/10–9 =
10, attenuation = 6.0 dB; and 6/10–9 = 11, attenuation = 10.4
dB (See Table 2).
The expander can be bypassed by setting bit 6/3 = 1.
Table 3 shows the various gain control settings which can
be accessed in Register 7. Table 4 is the volume control
settings, also located in Register 7.
Figures 23 through 31 illustrate the various characteristics
of the reveive audio path.
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
Table 2. Side Tone Attenuate Programming
Side Tone
Attenuate Bit #1
Side Tone
Attenuate Bit #0
Select #
Side Tone Attenuate
Amount at Expander Input
Side Tone Attenuate
Amount at Expander Output
0 0 0 0 dB 0 dB
0 1 1 1.5 dB 3.0 dB
1 0 2 3.0 dB 6.0 dB
1 1 3 5.2 dB 10.4 dB
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ
Table 3. Rx Gain Adjust Programming (Register 7)
Gain Control
Bit #4
Gain Control
Bit #3
Gain Control
Bit #2
Gain Control
Bit #1
Gain Control
Bit #0
Gain
Ctl #
Gain/Attenuation
Amount
– – – – – <6 –9.0 dB
0 0 1 1 0 6 –9.0 dB
0 0 1 1 1 7 –8.0 dB
0 1 0 0 0 8 –7.0 dB
0 1 0 0 1 9 –6.0 dB
0 1 0 1 0 10 –5.0 dB
0 1 0 1 1 11 –4.0 dB
0 1 1 0 0 12 –3.0 dB
0 1 1 0 1 13 –2.0 dB
ARCHIVE INFORMATION
ARCHIVE INFORMATION
Fr
eescale S
emiconduct
or
, I
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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