19-4950; Rev 0; 9/09
MAX9680 Evaluation Kit
General Description
The MAX9680 evaluation kit (EV kit) is a fully assembled
and tested surface-mount circuit board that evaluates
the MAX9680 IC. The MAX9680 is optimized for 3V
portable video applications and is specifically designed
to be compatible with video encoders embedded in
application processors with a 0.4V
P-P
video output. The
EV kit operates from a 2.7V to 3.6V single power supply.
The MAX9680 provides an internal fixed gain of 5.2V/V
and has an internal 2-pole reconstruction filter that typi-
cally has bandwidth (-3dB) of 9MHz and -18dB attenu-
ation at 27MHz. The MAX9680 EV kit accepts a 0.4V
P-P
input full-scale video signal and provides an output full-
scale video signal of 2V
P-P
(nominal).
S
Internal Preset Gain of 5.2V/V
S
Input Range Includes Ground
S
DC-Coupled Inputs and Outputs
S
Enable Input
S
Fully Assembled and Tested
S
Lead(Pb)-Free and RoHS Compliant
Features
S
Single 2.7V to 3.6V Supply Operation
Evaluates: MAX9680
Ordering Information
PART
TYPE
MAX9680EVKIT+
EV Kit
+Denotes
lead(Pb)-free and RoHS compliant.
Component List
DESIGNATION
QTY
DESCRIPTION
0.1FF
Q10%,
50V X7R ceramic
capacitor (0603)
Murata GRM188R71H104K
TDK C1608X7R1H104K
10FF
Q20%,
6.3V X7R ceramic
capacitor (0805)
Murata GRM21BR70J106K
TDK C2012X7R0J106K
75I BNC PCB vertical-mount
connectors
DESIGNATION
JU1, JU2
JU3, JU4
R1
R2, R3, R4
U1
—
QTY
2
2
1
0
1
1
DESCRIPTION
3-pin headers
2-pin headers
75I
Q1%
resistor (0603)
Not installed, resistors (0603)
Single-channel video-filter amplifier
(6 SC70)
Maxim MAX9680AXT+
PCB: MAX9680 EVALUATION KIT+
C1
1
C2
1
IN, OUT
2
Component Suppliers
SUPPLIER
Murata Electronics North America, Inc.
TDK Corp.
PHONE
770-436-1300
847-803-6100
WEBSITE
www.murata-northamerica.com
www.component.tdk.com
Note:
Indicate that you are using the MAX9680 when contacting these component suppliers.
_______________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
MAX9680 Evaluation Kit
Evaluates: MAX9680
Quick Start
• 2.7V to 3.6V, 500mA DC power supply (VDD)
• Video signal generator
• Video-measurement equipment (e.g., Tektronix
VM-700T)
The MAX9680 EV kit is fully assembled and test-
ed. Follow the steps below to verify board operation.
Caution: Do not turn on the power supply until all
connections are completed.
1) Connect the power-supply ground to the GND pad on
the EV kit.
2) Connect the 2.7V to 3.6V supply to the VDD pad on
the EV kit.
3) Connect the output of the video signal generator to
the IN BNC connector on the EV kit. The video signal
must be approximately 0 to 0.4V.
4) Connect the OUT BNC connector on the EV kit to the
input of the video measurement equipment.
5) Verify that a shunt is installed across pins 1-2 of
jumper JU1 (enabled).
6) Verify that a shunt is not installed across jumpers JU2,
JU3, and JU4.
7) Set the video signal generator for the desired video
input signal.
8) Turn on the power supply and enable the video signal
generator.
9) Analyze the video output signal with the VM-700T
video-measurement equipment.
Video input and output signals from the EV kit are
DC-coupled. The input of the EV kit can be directly con-
nected to the output of a video-current DAC and the EV
kit’s output has a 75I back-termination resistor.
The MAX9680 EV kit incorporates jumper JU1 to control
the enable input. When the enable input is set high, the
device is enabled. When the enable input is set low, the
device enters a low-power shutdown mode. See Table 1
for Jumper JU1 settings.
The MAX9680 EV kit circuit includes a 75I back-
termination resistor that limits short-circuit current when
an external short is applied to the video output. Jumper
JU3 is provided to apply an external short to GND at the
output to test this current-limiting feature.
The MAX9680 also features an internal output short-
circuit protection to prevent device damage in prototyp-
ing and applications where the amplifier output can be
directly shorted to ground. Jumper JU2 is provided to
test the internal output short-circuit protection.
The MAX9680 input is DC-coupled. When the sup-
ply voltage is between 2.7V and 3.6V, the input-volt-
age range extends from ground to 0.445V. When the
supply voltage is between 2.8V and 3.6V, the input-
voltage range extends from ground to 0.464V. A typical
current-output DAC that operates from a single supply
usually creates a composite video signal with a sync tip
very close to ground. Hence, the DAC output can be
directly connected to the MAX9680 input.
Input termination resistor R2 is provided, if necessary.
Jumper JU4 is provided to set the input to GND.
The MAX9680 EV kit connects directly to the video cable
through a 75I series back-termination resistor. The other
end of the cable should be properly terminated with a
75I resistor as well. Because of this configuration, the
peak-to-peak amplitude, as well as the DC level of the
signal, is divided by two. The MAX9680 output signal is
level-shifted up so the sync tip is approximately 130mV.
Recommended Equipment
Enable Input
Procedure
Short-Circuit Protection
Input Considerations
Detailed Description of Hardware
The MAX9680 EV kit is a fully assembled and tested
surface-mount circuit board that evaluates the MAX9680
IC. The MAX9680 is optimized for 3V portable video
applications and has an internal 2-pole reconstruction
filter that smoothes the steps and reduces the spikes on
the video signal from the video digital-to-analog convert-
er (DAC). The reconstruction filter typically has a band-
width (-3dB) of 9MHz and -18dB attenuation at 27MHz.
The MAX9680 provides an internal fixed gain of 5.2V/V.
The MAX9680 EV kit accepts a 0.4V
P-P
input full-scale
video signal and provides an output full-scale video sig-
nal of 2V
P-P
(nominal).
Output Consideration
Table 1. Jumper JU1 Settings
SHUNT
POSITION
1-2*
2-3
*Default
position.
ENABLE PIN
Connected to VDD
Connected to GND
OUTPUT
Enabled
Disabled
2
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