STV3208

STV3208 8 x 8 DISCRETE COSINE TRANSFORM (DCT) . . . . . . . . . . . 0 TO 27MHz PIXEL RATE IN SINGLE PRECISION MODE, 0 TO 20 MHz PIXEL RATE IN DOUBLE PRECISION MODE FORWARD AND INVERSE 8 x 8 TRANSFORM 9-BIT TWO’S COMPLEMENT PIXEL FORMAT 12-BIT TWO’S COMPLEMENT COEFFICIENT FORMAT OPTIMIZED ACCURACY FOR 8-BIT TWO’S COMPLEMENT PIXEL FORMAT SELECTABLE SCANNING OF COEFFICIENT BLOCKS FULLY TTL AND CMOS COMPATIBLE CMOS TECHNOLOGY SINGLE +5 VOLT POWER SUPPLY MAXIMUM POWER DISSIPATION : 750mW AT 27MHz DIP40 (Plastic Package) DESCRIPTION The STV3208 is a dedicated circuit for the 8 x 8 discrete cosine transform(DCT) computation.Twodimensional forward DCT (FDCT) or inverse DCT (IDCT) is performed for 8 x 8 block sizes and a pixel rate up to 27MHz. The circuit architecture is fully bidirectional with 9-bit magnitude pixel data bus and a 12-bit magnitude coefficient data bus programmed as input or output depending on the selection of FDCT or IDCT. FDCT Pixel Bus Coefficient Bus Input Output IDCT Output Input Data Format 9-bit 2’s Complement 12-bit 2’s Complement PQFP44 (Plastic Package) For the forward transform, the input pixels are coded on 9-bit 2’s complement and the output coefficients are coded on 12-bit 2’s complement. For the inverse transform, the data format is identical with the coefficients used as input and the pixels used as output. Two operating modes are provided : single precision mode at a pixel rate up to 27 MHz, and double precision mode at a pixel rate up to 20 M...