AD9980KSTZ-80 Analog Devices Inc, AD9980KSTZ-80 Datasheet - Page 41

• Manufacturer Part Number: AD9980KSTZ-80
• Description: IC,Data Acquisition Signal Conditioner,3-CHANNEL,8-BIT,CMOS,QFP,80PIN,PLASTIC
• Manufacturer: Analog Devices Inc

Specifications of AD9980KSTZ-80

• Applications: Video
• Interface: Analog
• Voltage - Supply: 3.13 V ~ 3.47 V
• Package / Case: 80-LQFP
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AD9980/PCBZ - KIT EVALUATION AD9980
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Adding a series resistor of value 50 Ω to 200 Ω can suppress
reflections, reduce EMI, and reduce the current spikes inside the
AD9980. If series resistors are used, place them as close to the
AD9980 pins as possible, (although try not to add vias or extra
length to the output trace to get the resistors closer).
If possible, limit the capacitance that each digital output drives
to less than 10 pF. This is easily accomplished by keeping traces
short and by connecting the outputs to only one device. Loading
the outputs with excessive capacitance increases the current
transients inside of the AD9980 and creates more digital noise
on its power supplies.
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Digital Inputs
Digital inputs on the AD9980 (HSYNC0, HSYNC1, VSYNC0,
VSYNC1, SOGIN0, SOGIN1, SDA, SCL and CLAMP) were
designed to work with 3.3 V signals, but are tolerant of 5.0 V
signals. Therefore, no extra components need to be added if
using 5.0 V logic.
Any noise that gets onto the Hsync input trace adds jitter to the
system. Therefore, minimize the trace length and do not run
any digital or other high frequency traces near it.
Reference Bypass
The AD9980 has three reference voltages that must be bypassed
for proper operation of the input PGA. REFLO and REFHI are
connected to each other through a 10 µF capacitor. REFCM is
connected to ground through a 10 µF capacitor. These refer-
ences are used by the input PGA circuitry to assure the greatest
stability. Place them as close to the AD9980 pin as possible.
Make the ground connection as short as possible.
AD9980