MT88E46AS Zarlink, MT88E46AS Datasheet - Page 13

• Manufacturer Part Number: MT88E46AS
• Description: Caller ID CMOS 3.58MHz 3.3V/5V 20-Pin SOIC Tube
• Manufacturer: Zarlink

Specifications of MT88E46AS

• Package: 20SOIC
• Telecommunication Standards Supported: Bellcore GR-30-CORE|SR-TSV-002476|TIA/EIA-716|TIA/EIA-777
• Fabrication Technology: CMOS
• Maximum Data Rate: 1.212 KBd
• Typical Operating Supply Voltage: 3.3|5 V
• Typical Supply Current: 4.3 mA
• Minimum Operating Temperature: -40 °C
• Maximum Operating Temperature: 85 °C
• Operating Frequency: 3.58 MHz

Data Sheet
Gain Setting Resistor Calculation for Nominal Vdd between 3 and 5V
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Example:
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For the desired nominal Vdd, use Figure 9 to calculate approximate Av.
For the GS1 op-amp, start with the 0dB gain setting resistor values of R5
are 53K6, 60K4 and 464K respectively. Keep R1, R2, R3, R4, C1, C2 as in Figure 8 to keep the input highpass
filter corner frequency constant for all gain settings.
For the desired Av:
Repeat for R10, R11 and R12 for the GS2 op-amp.
For the 3 V gain of -4.0 dB, Av = 0.63095.
R7
Av_actual is 294K/464K = 0.63362 or -3.96 dB.
R5
1/R6
-4dB
-4dB
R7
R5
1/R6
-4dB
Av
Av
= 0.63095 x 464K = 292.76K. The closest standard 1% resistor is 294K.
= 0.63362 x 53K6 = 33.96K. The closest standard 1% resistor is 34K0.
Av
= 1/34.0K - 1/294K = 1/38.45K. The closest standard 1% resistor is 38K3.
= R5
= R7
= 1/R5
0dB
0dB
x Av_actual
Av
x Av
Figure 9 - GS1 and GS2 Gain Ratios as a Function of Nominal Vdd
-1/R7
1.00
0.95
0.90
0.85
0.80
0.75
0.70
0.65
0.60
3.0
Av
0.63095
3.5
PRELIMINARY
Nominal Vdd (Volts)
Scaled for desired gain. Choose the closest standard 1% resistor
value as R7
Scaled for good common mode range. Choose the closest
standard 1% resistor as R5
Calculate R6
standard 1% resistor as R6
4.0
Av
Av
. Calculate Av_actual as R7
so that R5
4.5
0dB
Av
, R6
Av
Av
.
.
= R6
0dB
Av
and R7
|| R7
5.0
1.000
Av
0dB
Av
/R7
. Choose the closest
. In Figure 8 they
MT88E46
0dB
.
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