Catalog
Dual 12-Bit Buffered Multiplying CMOS D/A Converter
Key Features
• Two Matched 12-Bit DACs on One Chip
• Packaged in a Narrow 0.3" 24-Pin DIP
• Direct Parallel Load of all 12 Bits for High Data Throughput
• 12-Bit Endpoint Linearity (±1/2 LSB Over Temperature)
• On-Chip Latches for Both DACs
• +5V to +15V Single Supply Operation
• DACs Matched to 0.2% Typically
• Four-Quadrant Multiplication
• Improved ESD Resistance
• Available in Die Form
Description
AI
The DAC-8221 combines two identical 12-bit, multiplying, digital-to-analog converters into a single CMOS chip. This device is electrically similar to DAC-8212 with improved microprocessor interface timing and is packaged in a narrow 0.300" DIP. Monolithic construction offers excellent DAC-to-DAC matching and tracking over the full operating temperature range. The DAC-8221 consists of two thin-film R-2R resistor-ladder networks, two 12-bit data latches, one 12-bit input buffer, and control logic. The DAC-8221 operates on a single supply from +5V to +15V. Maximum power dissipation with 0V and +5V logic levels and a +5V supply is less than 0.5mW. The DAC-8221 is manufactured using PMI's highly-stable, thin film resistors on an advanced oxide-isolated, silicon-gate, CMOS process. PMI's improved latch-up resistant design eliminates the need for external protective Schottky diodes.A common 12-bit (TTL/CMOS compatible) input port is used to load a 12-bit-wide word into either of the two DACs. This port, whose data loading is similar to that of a RAM's write cycle, interfaces directly with most 12-bit or wider bus systems. WithWRandCSlines at logic LOW, the input data registers are transparent. This allows direct unbuffered data to flow directly to the DAC output selected byDAC A/DAC B control input.