Datasheet

DC Power Connectors

The VCC and GND power connectors should be powered with a DC input voltage of 3.3V ± 5% (3.6V maximum).

JP2 Controls

¯¯¯

JP2 allows monitoring of the Carrier Detect (CD

¯¯¯

) at the BNC_IO pin while in the input mode (equalizer). CD

¯¯¯

asserted low when an input signal is detected at the BNC_IO pin, and high when no input signal is present.

TX_EN

JP2 allows control of the TX_EN pin to enable or disable the cable driver. The LMH0387 TX_EN pin has an

internal pullup to enable the cable driver by default, so this pin may be left unconnected when using the LMH0387

in the output mode. To disable the cable driver, place a jumper to tie TX_EN to GND. When using the LMH0387 in

the input mode, the cable driver must be disabled by tying TX_EN low. TX_EN may optionally be controlled via the

GUI using the SPA dongle as described below.

SD/HD

¯¯¯

JP2 allows control of the SD/HD

¯¯¯

pin for setting the slew rate for the BNC_IO pin while the LMH0387 is in the output

mode (cable driver). This pin may be connected to GND for the faster HD/3G slew rate or connected to V

for the

slower SD slew rate. The LMH0387 SD/HD

¯¯¯

pin has an internal pulldown to enable the HD/3G slew rate by default.

SPI Header (JP1)

JP1 is the SPI (Serial Peripheral Interface) header. It allows access to the SPI pins ( SS

¯¯¯

, MISO, MOSI, and SCK)

to control the SPI registers of the LMH0387 equalizer. To use the SPI interactive GUI, plug the 6-pin parallel cable

between this header and JP7 on the SPA dongle to connect the pins one-for-one as shown in Table 1. The SPA

dongle requires special software and must be connected to the PC via the USB – see the Software Setup section.

TABLE 1. SPI Connections between SD387 and SPA Dongle

SD387 JP1 SPA Dongle JP7

Pin # Name

1 GND

2 SCK

2 MCK

3 MOSI

4 MISO

4 MOSI

5 SS

6 GND

Carrier Detect LED (D1)

D1 shows the status of Carrier Detect at the LMH0387 equalizer input. This LED is GREEN when an input signal

has been detected at the BNC_IO pin, and OFF when no input is detected.

SD387EVK User Guide 3 of 23