XRD8775 Datasheet, PDF (1/15 Pages) Exar Corporation – CMOS 8-Bit High Speed Analog-to-Digital Converter

XRD8775
CMOS 8-Bit High Speed
Analog-to-Digital Converter
FEATURES
· 8-Bit Resolution
· Up to 20MHz Sampling Rate
· Internal S/H Function
· Single Supply: 5V
· V_IN DC Range: 0V to V_DD
· V_REF DC Range: 1V to V_DD
· Low Power: 75mW typ. (excluding reference)
· Latch-Up Free
· ESD Protection: 2000V Minimum
April 2002-4
· 3V Version: XRD87L75
· Small 20-Pin SOIC/SSOP Packages
APPLICATIONS
· Digital Color Copiers
· Cellular Telephones
· CCD-Based Systems
· Hardware Scanners
· Video Capture Boards
GENERAL DESCRIPTION
The XRD8775 is an 8-bit Analog-to-Digital Converter in
a small 20-pin SOIC/SSOP package. Designed using
an advanced 5V CMOS process, this part offers excel-
lent performance, low power consumption and latch-up
free operation.
This device uses a two-step flash architecture to
maintain low power consumption at high conversion
rates. The input circuitry of the XRD8775 includes an
on-chip S/H function and allows the user to digitize
analog input signals between AGND and AV_DD. Careful
design and chip layout have achieved a low analog input
capacitance. This reduces “kickback” and eases the
requirements of the buffer/amplifier used to drive the
XRD8775.
SIMPLIFIED BLOCK AND TIMING DIAGRAM
The designer can choose the internally generated
reference voltages by connecting V_RB to V_RBS and V_RT to
V_RTS , or provide external reference voltages to the V_RB
and V_RT pins. The internal reference generates 0.6V at
V_RB and 2.6V at V_RT. Providing external reference
voltages allows easy interface to any input signal range
between GND and V_DD. This also allows the system to
adjust these voltages to cancel zero scale and full
scale errors, or to change the input range as needed.
The device operates from a single +5V supply. Power
consumption is 75mW at F_S = 15MHz.
Specified for operation over the commercial / industrial
(-40 to +85°C) temperature range, the XRD8775 is
available in Surface Mount (SOIC), Shrink Small Out-
line (SSOP) and Plastic Dual-In-line (PDIP) Packages.
Rev. 4.00
EXAR Corporation, 48720 Kato Road, Fremont, CA 94538 • [phone] • FAX [phone]