Evaluation board

AN2526

4/10

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Video inputs conditioning

The blanking level might vary between different video transmitters. This STMAV340

evaluation board can handle video signals with blanking level of 0 V to 2.5 V.

If video signals blanking level at outside the above range, some input conditioning should be

done to translate the blanking level to the range specified.

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Digital control signals

Table 2.

Video ports on the STMAV340 Demo board

Designator

Notes

VGA1

– Connect to VGA source from PC.

– When SEL ‘0’ this port is active

– JP1 to JP4 closed.

– JP5 to JP8 open.

VGA2

– Connect to VGA source from PC

– When SEL ‘1’ this port is active

– JP1 to JP4 open.

– JP5 to JP8 closed.

CVBS1

– Connect to CVBS source

– When SEL ‘0’ this port is active

CVBS2

– Connect to CVBS source

– When SEL ‘1’ this port is active

VGA_OUT

Active VGA input is directed to this port. Connect to a display unit.

CVBS_OUT

Active CVBS input is directed to this port. Connect to a display unit.

Table 3.

Control signals on the STMAV340 Demo board

Signal

Function

Notes

OE

Enable or disable the

output.

JP9 close = LOW (enable)

JP9 open = HIGH (disable)

SEL

Select which switch is

activated.

JP10 close = LOW (VGA1, CVBA1)

JP10 open = HIGH

(VGA2, CVBS2)