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DS21354 & DS21554
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Signal Name:
TTIP & TRING
Signal Description:
Transmit Tip and Ring
Signal Type:
Output
Analog line driver outputs. These pins connect via a step–up transformer to the E1 line. See Section 0 for
details.
4.1.7 Supply Pins
Signal Name:
DVDD
Signal Description:
Digital Positive Supply
Signal Type:
Supply
5.0 volts +/-5% (DS21554) or 3.3 volts +/-5% (DS21354). Should be tied to the RVDD and TVDD pins.
Signal Name:
RVDD
Signal Description:
Receive Analog Positive Supply
Signal Type:
Supply
5.0 volts +/-5% (DS21554) or 3.3 volts +/-5% (DS21354). Should be tied to the DVDD and TVDD pins.
Signal Name:
TVDD
Signal Description:
Transmit Analog Positive Supply
Signal Type:
Supply
5.0 volts +/-5% (DS21554) or 3.3 volts +/-5% (DS21354). Should be tied to the RVDD and DVDD pins.
Signal Name:
DVSS
Signal Description:
Digital Signal Ground
Signal Type:
Supply
0.0 volts. Should be tied to the RVSS and TVSS pins.
Signal Name:
RVSS
Signal Description:
Receive Analog Signal Ground
Signal Type:
Supply
0.0 volts. Should be tied to DVSS and TVSS.
Signal Name:
TVSS
Signal Description:
Transmit Analog Signal Ground
Signal Type:
Supply
0.0 volts. Should be tied to DVSS and RVSS.
5 PARALLEL PORT
The DS21354/554 is controlled via either a non–multiplexed (MUX = 0) or a multiplexed (MUX = 1) bus
by an external microcontroller or microprocessor. The device can operate with either Intel or Motorola
bus timing configurations. If the BTS pin is tied low, Intel timing will be selected; if tied high, Motorola
timing will be selected. All Motorola bus signals are listed in parenthesis (). See the timing diagrams in
the A.C. Electrical Characteristics in Section 21 for more details.