Filter
Top Products
Evaluation Board for Quad T1/E1 Applications — LXD386
Developer Manual 9
3.0 Hardware Mode Set-Up and Operation
3.1 Power 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.
3.2 Hardware 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 20-pin sockets JP4
and JP6.
3.3 Loopback 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.
3.4 Clock 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.
Table 1. LOOP/DLOOP Switch Settings
LOOPn DLOOPn Channel #n Operation
Open x Normal Mode
LOW x Remote Loopback
HIGH LOW Analog Local Loopback
HIGH HIGH Digital Local Loopback
1. “x” means “don’t care”