Evaluation Board for Quad T1/E1 Applications — LXD386
3.0Hardware Mode Set-Up and Operation
3.1Power Connections
The evaluation board has two power planes (VCC and TVCC) each of which is tied to a separate red colored banana jack.
1.Connect the +3.3 VDC power supply to the VCC jack.
2.Connect either a +3.3 VDC or +5.0 VDC power supply to the TVCC jack.
3.Connect the power supply ground lead(s) to the black (GND) banana jack.
Jumper JP1 is provided to allow LXT386 current consumption measurements and must be installed for normal board operation. Jumper JP3 allows measurement of the current in the TVCC power supply only. It must also be installed for normal operation.
3.2Hardware Mode Selection
To enable the Hardware mode of operation:
1.Set the MODE switch in switch block S1 to the LOW position.
2.Insert the two shorting blocks, provided with the evaluation board kit, into
3.3Loopback Mode Selection
The LXT386 LOOP/DLOOP signals are set by switches in switch block S1. Depending on the LOOPn/DLOOPn combination selected for a particular channel, a different operation or loopback mode is selected. Please refer to Table 1.
Table 1. LOOP/DLOOP Switch Settings
LOOPn | DLOOPn | Channel #n Operation |
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|
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Open | x | Normal Mode |
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|
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LOW | x | Remote Loopback |
|
|
|
HIGH | LOW | Analog Local Loopback |
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|
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HIGH | HIGH | Digital Local Loopback |
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|
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1. “x” means “don’t care”
3.4Clock Edge Selection
The phase relation between RCLK and RPOS/RNEG is set by the CLKE switch in switch block S4. Please refer to the “CLKE” signal pin in the LXT386 data sheet for details.
Developer Manual | 9 |
