Renesas ISL59481EVAL1Z User Manual

ISL59481EVAL1Z
Evaluation Board
Introduction
The ISL59481EVAL1Z evaluation board contains the
ISL59481 Dual 4:1 RGB MUX amp and associated
components needed to implement an 8:1 RGB+H/V sync
video multiplexer. The 8 video input ports, and single output
port are accessed using standard 15 pin VGA female
connectors. The I/O connectors are compatible with most
VGA, SVGA and XGA video sources and video monitors with
VGA cable interfaces. A typical application would use the
ISL5948XEVAL1Z board to multiplex anywhere from 2 to 8
PC's or laptops to a single video monitor or projector.
Evaluation Board Description and Key Features
The multiplexing of the RGB video is performed by the
ISL59481. Multiplexing the H and V sync signals is
accomplished using two ISL84051 8:1 analog switches. The
ISL59481 Video MUX and the analog H and V sync
multiplexers have the same input channel select logic
coding, and are parallel-connected to form a single 3 input
binary coded interface (S0, S1, S2). An additional ISL84051
8:1 analog switch and channel-select LED indicators are
included to identify the selected input channel. The
evaluation board contains three different channel select
options via jumpers on the board. Switches on the board
enable direct logic control in binary format. The on-board
oscillator and 4-bit counter can be connected to provide a
Evaluation Board Jumper, Cable Header, and Switch Descriptions
COMPONENT
JUMPERS
J1 Selects channel select via single-step momentary contact switch S4, or auto mode using on-board oscillator
J-S0 Selects S0 logic input to manual control via switch S0 or through external control ribbon cable header
J-S1 Selects S1 logic input to manual control via switch S1 or through external control ribbon cable header
J-S2 Selects S2 logic input to manual control via switch S2 or through external control ribbon cable header
HEADERS
EN External MUX enable: Internal pull-down (logic 0) enables RGB+H/V output, logic high disables RGB and H/V sync output
S0 External S0 channel select logic input
S1 External S1 channel select logic input
S2 External S2 channel select logic input
SWITCHES
S0 Manual channel select logic input S0
S1 Manual channel select logic input S1
S2 Manual channel select logic input S2
S3 Momentary contact channel select step control
AN1320 Rev 0.00
May 3, 2007
USER'S MANUAL
continuous channel-by-channel scan of as few as 2 input
channels and as many as 8 input channels (Table 2). A
jumper option allows the user to disconnect the auto-scan
oscillator and use the on-board momentary-contact switch to
manually scan through the selected channels.
Reference Documents
• Data Sheet FN6394 "Dual, 500MHz Triple, Multiplexing
Amplifiers"
Getting Started
The evaluation board should have the same appearance as
the silk screen shown in Figure 1. Prior to applying power,
connect the source input VGA cables and the evaluation
board output VGA cable to the respective video
components. The evaluation board, as supplied, is designed
for 75 source impedances and requires a 75 termination
impedance in the output display device.
Applying Power to the Evaluation Board
The following safeguards will ensure correct power-up.
1. Limit the current on ±5V supplies to 250mA.
2. Turn on the power supplies after the power cables are
attached to the evaluation board.
Power supply protection Schottky diodes are included on the
±5V supplies to prevent damage due to reverse polarity.
DESCRIPTION
AN1320
Rev 0.00
May 3, 2007
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