mc33411a Freescale Semiconductor, Inc, mc33411a Datasheet - Page 34

• Manufacturer Part Number: mc33411a
• Description: 900 Mhz Analog Cordless Phone Baseband With Compander
• Manufacturer: Freescale Semiconductor, Inc

( 1.5 V) which is available at Pin 37. The value read back
from the LBD A/D will therefor be approximately:
and for the RSSI
–105
–110
–115
–120
–125
N(for LBD)
N(for RSSI)
34
These values are compared to the internal reference VB
0.01
Adjust Bit #20
V CC = 3.6 V
T A = 25 C
V ref
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
C In to E Out versus VB Capacitor
Crosstalk
Figure 50. Crosstalk/Noise from
2.5(VB)(1.07)
63 (RSSIVoltage)
63 (V
0.1
(VB)(1.07)
VB CAPACITOR (µF)
CC
Adjust Bit #19
)
Noise
V ref
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
1.0
Table 8. VB Voltage Reference Programming
Adjust Bit #18
V ref
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
MC33411A/B
10
(27)
(28)
–87
–92
–97
–102
–107
VB Voltage Adjust and Characteristics
adjusted over a
adjustment steps will be
desired, VB can be used to bias external circuitry, as long as
the load current on this pin does not exceed 10 µA. V B varies
by less than 0.5% over supply voltage, referenced to V CC =
3.6 V.
to ground affects both the noise and crosstalk from the
receive and transmit audio paths, so the value should be
chosen with caution. Figures 50 and 51 show this
relationship.
–50
–55
–60
–65
–70
–75
–80
–85
–90
–95
Adjust Bit #17
0.01
VB has a production tolerance of
The value of the de–coupling capacitor connected from VB
V ref
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
Crosstalk, 130 Ω load
V CC = 3.6 V
T A = 25 C
Crosstalk, no load
E In to Tx Out versus VB Capacitor
Figure 51. Crosstalk/Noise from
0.1
9% range using bits 3/20–17. The
Adjust #
VB CAPACITOR (µF)
V ref
Noise
10
11
12
13
14
15
MOTOROLA RF/IF DEVICE DATA
0
1
2
3
4
5
6
7
8
9
1.2% each (See Table 8). If
Adjustment Amount
1.0
Voltage Reference
8%, and can be
–9.0%
–7.8%
–6.6%
–5.4%
–4.2%
–3.0%
–1.8%
–0.6%
0.6%
1.8%
3.0%
4.2%
5.4%
6.6%
7.8%
9.0%
10
–61
–63
–65
–67
–69
–71
–73
–75