Bt473

The Bt473 true-color RAMDAC is designed specifically for true-color computer graphics.Bt473 has three 256 * 8 color lookup tables with triple 8-bit video D/A converters to support 24-bit true-color,8-bit true-color,and 15-bit true-color operations are supported.Features include a programmable pedestal (0 or 7.5 IRE) and optional on-chip voltage reference.The 15 overlar registers provide,for example,overlaying curors,grids,menus,and EGA emulation.Also Bt473 supported are a pixel read mask register and sync generation on all three channels.An external current reference,an external voltage reference,or the internal voltage reference may be used.The Bt473 generates RS-343A-compatible video signals into a doubly-terminated 75 load.Differential and integral linearity errors are guaranteed to be a maximum of ±1 LSB over the full temperature range.

The Bt473 has some absolute maximum ratings.When parameter of Bt473 is VAA (measured to GND),the max is 7.0,the unit is V.When parameter is voltage on any signal pin,the min is GND-0.5,the max is VAA+0.5,the units is V.When parameter is analog output short circuit duration to any power supply or common,the symbol is ISC,the typ is indefinite.When parameter is ambient operating temperature,the symbol is TA,the min is -55,the max is +125,the unit is .When parameter is storage temperature,the symbol is TS,the min is -65,the max is +150,the unit is .When parameter is junction temperature,the symbol is TJ,the max is +150,the unit is .When parameter is vapor phase soldering (1 minute),the symbol is TVSOL,the max is 220,the unit is .