Dual 12-Bit (8-Bit Byte) a Double-Buffered CMOS D/A Converter DAC8248 PIN CONNECTIONS FEATURES Two Matched 12-Bit DACs on One Chip 24-Pin 0.3 Cerdip (W Suffix), 12-Bit Resolution with an 8-Bit Data Bus 24-Pin Epoxy DIP (P Suffix), Direct Interface with 8-Bit Microprocessors 24-Pin SOL (S Suffix) Double-Buffered Digital Inputs RESET to Zero Pin 12-Bit Endpoint Linearity (61/2 LSB) Over Temperature 15 V to 115 V Single Supply Operation Latch-Up Resistant Improved ESD Resistance Packaged in a Narrow 0.3 24-Pin DIP and 0.3 24-Pin SOL Package Available in Die Form APPLICATIONS Multichannel Microprocessor-Controlled Systems Robotics/Process Control/Automation Automatic Test Equipment Programmable Attenuator, Power Supplies, Window Comparators The DAC8248s double-buffered digital inputs allow both Instrumentation Equipment DACs analog output to be updated simultaneously. This is par- Battery Operated Equipment ticularly useful in multiple DAC systems where a common LDAC signal updates all DACs at the same time. A single RESET pin resets both outputs to zero. GENERAL DESCRIPTION The DAC8248 is a dual 12-bit, double-buffered, CMOS digital- The DAC8248s monolithic construction offers excellent DAC- to-DAC matching and tracking over the full operating tempera- to-analog converter. It has an 8-bit wide input data port that inter- ture range. The DAC consists of two thin-film R-2R resistor faces directly with 8-bit microprocessors. It loads a 12-bit word in two bytes using a single control it can accept either a least signifi- ladder networks, two 12-bit, two 8-bit, and two 4-bit data regis- ters, and control logic circuitry. Separate reference input and cant byte or most significant byte first. For designs with a 12-bit or feedback resistors are provided for each DAC. The DAC8248 16-bit wide data path, choose the DAC8222 or DAC8221. (continued on page 4) FUNCTIONAL BLOCK DIAGRAM REV. B Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Tel: 617/329-4700 Fax: 617/326-8703DAC8248SPECIFICATIONS ( V = +5 V or +15 V V = V = +10 V V = V = 0 V AGND = DGND = 0 V DD REF A REF B OUTA OUT B ELECTRICAL CHARACTERlSTICS T = Full Temp Range specified in Absolute Maximum Ratings unless otherwise noted. Specifications apply for DAC A and DAC B.) A DAC8248 Parameter Symbol Conditions Min Typ Max Units STATIC ACCURACY Resolution N 12 Bits Relative Accuracy INL DAC8248A/E/G 1/2 LSB DAC8248F/H 1 LSB Differential Nonlinearity DNL All Grades are Guaranteed Monotonic 1 LSB 1 Full-Scale Gain Error G DAC8248A/E 1 LSB FSE DAC8248G 2 LSB DAC8248F/H 4 LSB Gain Temperature Coefficient (Gain/Temperature) TCG (Notes 2, 3) 2 5 ppm/C FS All Digital Inputs = 0s Output Leakage Current I T = +25C 5 10 LKG A I (Pin 2), I (Pin 24) T = Full Temperature Range 50 nA OUT A OUT B A Input Resistance (V , )R (Note 4) 8 11 15 k REF A REF B REF R REF Input Resistance Match 0.2 1% R REF DIGITAL INPUTS Digital Input High V V = +5 V 2.4 V INH DD V = +15 V 13.5 V DD Digital Input Low V V = +5 V 0.8 V INL DD V = +15 V 1.5 V DD Input Current (V = 0 V T = +25C 0.001 1 A IN A or V and V or V)I T = Full Temperature Range 10 A DD INL INH IN A Input Capacitance C DB0DB11 10 pF IN (Note 2) WR, LDAC, DAC A/DAC B, LSB/MSB, RESET 15 pF POWER SUPPLY Supply Current I Digital Inputs = V or V 2mA DD INL INH Digital Inputs = 0 V or V 10 100 A DD DC Power Supply Rejection Ratio PSRR V = 5% DD (Gain/V ) 0.002 %/% DD 2 AC PERFORMANCE CHARACTERISTICS 5, 6 Propagation Delay t T = +25C 350 ns PD A 6, 7 Output Current Setting Time t T = +25C1s S A Output Capacitance C Digital Inputs = All 0s O C , C 90 pF OUT A OUT B Digital Inputs = All 1s C , C 120 pF OUT A OUT B AC Feedthrough at FT V to I V = 20 V p-p A REF A OUT A REF A I or I f = 100 kHz T = +25C 70 dB OUT A OUT B A FT V to I V = 20 V p-p B REF B OUT B REF B f = 100 kHz T = +25C 70 dB A 2 REV. B