73M1903-IVT/F Maxim Integrated Products, 73M1903-IVT/F Datasheet - Page 23

• Manufacturer Part Number: 73M1903-IVT/F
• Description: IC MODEM AFE V.22BIS 20-TSSOP
• Manufacturer: Maxim Integrated Products

Specifications of 73M1903-IVT/F

• Number Of Channels: 2
• Voltage - Supply, Analog: 3 V ~ 3.6 V
• Voltage - Supply, Digital: 3 V ~ 3.6 V
• Package / Case: 20-TSSOP (0.173", 4.40mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power (watts): -
• Number Of Bits: -

5.2
5.3
DS_1903_032
To calculate the analog output power, the peak voltage is calculated and the peak to rms ratio (crest
factor) must be known. The following formula is used to calculate the output power, in dBm referenced to
600 Ω.
Pout (dBm) = 10 * log [ ( Vout (V) / cf )
The following example demonstrates the calculation of the analog output power given a 1.2 kHz FSK tone
(sine wave) with a peak code word value of 11,878 sent out by the DSP.
The differential output voltage at TXAP-TXAN will be:
With FreqFctr = 1.02, (See
Vout (V) = 2 * (11,878/32,767) * 0.6640625 * 0.8889 * 1.36 * 1.0 * 1.4454 * 1.02 = 0.841 V
The output signal power will be:
Pout (dBm) = 10 * log [(0.841 / 1.41)
Reset State 08h
Bit 7
ENFE
ENFE
TXBST1
TXBST0
TXDIS
RXG1:0
RXGAIN
Rev. 2.1
Transmit Power - dBm
Control Register (CTRL1): Address 00h
Bit 6
Unused
1 = Enable the digital filters and analog front end.
0 = Disable the analog blocks shut off the clocks to the digital and analog receive/transmit
1 = Add a gain of 1.335 dB (16.6%) to the transmitter; also the common mode voltage of the
0 = No gain is added
1 = A gain of 1.65 dB (21%) is added to the transmitter
0 = The gain of the transmitter is nominal
1 = Tri-state the TXAP and TXAN pins, provides a bias of VBG into 80 kΩ for each output pin
These bits control the receive gain as shown in
1 = Increase the gain of the receiver by 20 dB.
circuits.
transmit path is increased to 1.375 V. This is intended for enhancing DTMF transmit
power only and should not be used in data mode.
Table 13: Peak to RMS Ratios for Various Modulation Types
Bit 5
TXBST1
Transmit Type
Figure
DPSK
DTMF
QAM
V.90
FSK
10)
Bit 4
TXBST0
2
/ (0.001 * 600) ] = - 2.29 dBm.
2
/ ( 0.001 * 600 ) ]
Crest Factor
Bit 3
TXDIS
1.81
2.31
1.41
1.99
4.0
Bit 2
RXG1
Table 12.
Max Line Level
-5.7 dBm
-12 dBm
-9 dBm
-9 dBm
-9 dBm
Bit 1
RXG0
Bit 0
RXGAIN
73M1903 Data Sheet
pk
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