MAX11500 Evaluation Kit
The video inputs and outputs can also be configured
for DC-coupled operation. The MAX11500 EV kit video
inputs have a 75Ω termination to ground and the out-
puts are 75Ω back terminated.
Quick Start
Recommended Equipment
Before beginning, the following equipment is needed:
• 5V, 200mA DC power supply (V
)
CC
Jumper Selection
• Video signal generator (e.g., Tektronix TG-2000 or
TG-700)
AC-/DC-Coupled Input Operation
The MAX11500 features a transparent clamp at the video
inputs that allows for either AC- or DC-coupling. If the
input signal remains above ground, the transparent
clamp is inactive, offering true DC-input coupling. If the
signal goes below ground, it must be AC-coupled. The
transparent clamp will set the sync tip just below ground.
• Video measurement equipment (e.g., Tektronix
VM-6000 or equivalent)
Procedure
The MAX11500 EV kit is fully assembled and tested.
Follow the steps below to verify board operation.
Caution: Do not turn on the power supply until all
connections are completed.
Jumpers JU1, JU3, and JU5 set the MAX11500 EV kit
video inputs for AC- or DC-coupled operation. For AC-
coupled operation, remove shunts from jumpers JU1,
JU3, and JU5. For DC-coupled operation, install shunts
across jumpers JU1, JU3, or JU5. Use DC-coupling
only for input signals whose lowest voltage is above
ground. See Table 1 for proper jumper settings. When
interfacing DC-coupled signals to the MAX11500 EV kit
VIDIN_ inputs, verify that shunts are not installed across
jumpers JU2, JU4, or JU6.
1) Connect the video signal generator output to the
VIDIN_ BNC connectors on the MAX11500 EV kit.
2) Connect the VIDOUT_ BNC connectors on the EV kit
to the input of the video measurement equipment.
3) Connect the power-supply ground to the GND pad
on the EV kit.
Evluates:MAX150
4) Connect the 5V supply to the VCC pad on the EV kit.
5) Verify that no shunts are installed across jumpers
JU1, JU3, JU5, JU7, JU8, and JU9 (AC-coupled
inputs and outputs), and JU2 (no DC bias at VIDIN1).
Table 1. AC-/DC-Coupled Input Operation
(JU1, JU3, and JU5)
SHUNT POSITION
Not installed
Installed
EV KIT INPUTS
6) Install shunts across jumpers JU4 and JU6 (DC
bias for VIDIN2 and VIDIN3).
AC-coupled operation
DC-coupled operation
7) Set the video signal generator for the desired video
input signal using a YP P signal format.
B R
DC Bias for YP P Signals
B R
8) Connect the Y signal to the VIDIN1 BNC connector,
When configuring the EV kit video inputs for AC-
coupled operation, the correct DC bias point has to be
chosen, depending on the input signal. Unipolar signals,
such as R, G, B, and Y, are biased correctly using the
MAX11500 internal transparent clamp. For bipolar sig-
and P and P to VIDIN2 and VIDIN3, respectively.
B
R
9) Turn on the power supply and enable the video signal
generator output.
10) Analyze the video output signal with the video mea-
surement equipment.
nals, such as P and P signals, a constant DC bias volt-
B
R
age has to be applied after the AC-coupling capacitor to
make sure that the clamp never operates. A 590mV DC
bias voltage can be applied by installing shunts across
jumpers JU2, JU4, or JU6. To configure the inputs to a
different DC bias voltage, replace resistors R2, R5, or R8.
See Table 2 for input clamp configuration.
Detailed Description
The MAX11500 EV kit is a fully assembled and tested
surface-mount PCB that contains a MAX11500 IC. The
MAX11500 is a 3-channel video filter for reconstruction
and anti-aliasing applications. All 3 channels have iden-
tical characteristics.
Table 2. Input Clamp Operation (JU2,
JU4, and JU6)
The MAX11500 filter’s -3dB frequency is 33MHz. The
device includes a +6dB output buffer capable of dri-
video signal into a standard 150Ω load. In
the default configuration, the MAX11500 EV kit video
inputs and outputs are set for AC-coupled operation.
ving a 2V
P-P
SHUNT
EV KIT FUNCTION
POSITION
Installed
DC bias enabled: Use for P , P signals
B R
Not installed
DC bias disabled: Use for R, G, B, Y signals
2
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