Manufacturer Part NumberDAC128S085
ManufacturerTexas Instruments
DAC128S085 datasheet

Specifications of DAC128S085

Resolution(bits)12Dac: Channels8
InterfaceSerial SPIOutput TypeVoltage
Output Range Max.(v Or Ma)5.5Settling Time(µs)8
Reference: TypeExtPower Consumption(typ)(mw)1.95
Pin/package16SON, 16TSSOP, 16WQFN, 16WSON  
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DAC128S085 12-Bit Micro Power OCTAL Digital-to-Analog Converter with
Rail-to-Rail Outputs
Literature Number: SNAS407D

DAC128S085 Summary of contents

  • Page 1

    ... DAC128S085 DAC128S085 12-Bit Micro Power OCTAL Digital-to-Analog Converter with Rail-to-Rail Outputs Literature Number: SNAS407D ...

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    ... The DAC128S085 is a full-featured, general purpose OCTAL 12-bit voltage-output digital-to-analog converter (DAC) that can operate from a single +2.7V to +5.5V supply and con- sumes 1. and 4. 5V. The DAC128S085 is packaged in a 16-lead LLP package and a 16-lead TSSOP package. The LLP package makes the DAC128S085 the smallest OCTAL DAC in its class ...

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    Block Diagram www.national.com 2 30016903 ...

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    ... Exposed die attach pad can be connected to ground or left floating. Ground Soldering the pad to the PCB offers optimal thermal performance and enhances package self-alignment during reflow. 3 30016902 Description is utilized in daisy chain operation and is OUT pin on another DAC128S085. Data is IN unless SYNC remains low for more than 16 www.national.com ...

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    Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage Voltage on any Input Pin Input Current at Any Pin (Note 3) Package Input Current ...

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    Symbol Parameter Output Short Circuit Current (sink (Note 10) Continuous Output Current per I O channel (Note 9) C Maximum Load Capacitance Output Impedance OUT REFERENCE INPUT CHARACTERISTICS Input Range Minimum Input Range Maximum VREF1,2 ...

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    Symbol Parameter Total Power Consumption (output P N unloaded) Total Power Consumption in all PD P Modes, PD (Note 9) A.C. and Timing Characteristics The following specifications apply for 4047. Boldface limits apply for T Symbol Parameter ...

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    Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the ...

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    ... REF Transfer Characteristic www.national.com where V the DAC resolution in bits, which is 12 for the DAC128S085. MAXIMUM LOAD CAPACITANCE is the maximum capaci- tance that can be driven by the DAC with output stability maintained. MONOTONICITY is the condition of being monotonic, where the DAC has an output that never decreases when the input code increases ...

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    Typical Performance Characteristics unless otherwise stated INL vs Code INL/DNL vs V REF INL/DNL +2.7V to +5.5V REF1,2 30016952 INL/DNL vs f 30016957 INL/DNL vs Temperature 30016922 ...

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    Zero Code Error vs. V Zero Code Error vs. f Full-Scale Error vs. V www.national.com A 30016930 Zero Code Error vs. Temperature SCLK 30016934 A 30016937 10 Zero Code Error vs. V REF 30016931 30016936 Full-Scale Error vs. V REF ...

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    Full-Scale Error vs. f SCLK 30016933 I vs 30016944 I vs. V VREF REF 30016925 Full-Scale Error vs. Temperature I vs. Temperature VA I vs. Temperature VREF 11 30016939 30016945 30016935 www.national.com ...

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    Settling Time Wake-Up Time Power-On Reset www.national.com Glitch Response 30016928 DAC-to-DAC Crosstalk 30016951 Multiplying Bandwidth 30016947 12 30016946 30016938 30016950 ...

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    ... Functional Description 1.1 DAC ARCHITECTURE The DAC128S085 is fabricated on a CMOS process with an architecture that consists of switches and resistor strings that are followed by an output buffer. The reference voltages are externally applied at V for DAC channels A through D and REF1 V for DAC channels E through H. ...

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    ... Subsequently, the next sixteen falling edges of SCLK will output the first six- teen data bits entered into D three DAC128S085s in Figure 6. In this instance, It takes forty-eight falling edges of SCLK followed by a rising edge of SYNC to load all three DAC128S085s with the appropriate register data ...

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    ... When the DAC128S085 first powers up, the DAC is in WRM. In WRM, the registers of each individual DAC channel can be written to without causing the DAC outputs to be updated. This is accomplished by setting DB15 to "0", specifying the DAC register to be written to in DB[14:12], and entering the new DAC register setting in DB[11:0] (see Table 2) ...

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    ... This section will present the step-by-step instructions for pro- gramming the serial input register. 2.1.1 Updating DAC Outputs Simultaneously When the DAC128S085 is first powered on, the DAC is op- erating in Write Register Mode (WRM). Operating in WRM allows the user to program the registers of multiple DAC channels without causing the DAC outputs to be updated ...

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    ... LM4132 The LM4132, with its ±0.05% accuracy over temperature good choice as a reference source for the DAC128S085. The 4.096V version is useful 4.095V output range is desirable. Bypassing the LM4132 voltage input pin with a 4.7µF capacitor and the voltage output pin with a 4.7µF ca- pacitor will improve stability and reduce output noise ...

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    ... VARIABLE CURRENT SOURCE OUTPUT The DAC128S085 is a voltage output DAC but can be easily converted to a current output with the addition of an opamp. In Figure 13, one of the channels of the DAC128S085 is con- verted to a variable current source capable of sourcing up to 40mA. www.national.com ...

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    ... CM amplifier stage and thus becomes the bias voltage for the in- put of the ADC121S705. Channel B of the DAC128S085 is providing the reference voltage to the ADC121S705. The ref- erence for the ADC121S705 may be set to any voltage from 1V to 5V, providing the widest dynamic range possible. ...

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    ... Interface A serial interface between the DAC128S085 and the 68HC11 microcontroller is shown in Figure 19. The SYNC line of the DAC128S085 is driven from a port line (PC7 in the figure), similar to the 80C51/80L51. The 68HC11 should be configured with its CPOL bit as a zero and its CPHA bit as a one. This configuration causes data on the MOSI output to be valid on the falling edge of SCLK ...

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    ... The power supply for the DAC128S085 should only be used for analog circuits also advisable to avoid the crossover of analog and digital signals. This helps minimize the amount of noise from the ...

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    ... Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 16-Lead LLP Order Numbers DAC128S085CISQ NS Package Number SQA16A 16-Lead TSSOP Order Numbers DAC128S085CIMT NS Package Number MTC16 22 ...

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    Notes 23 www.national.com ...

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    For more National Semiconductor product information and proven design tools, visit the following Web sites at: Products Amplifiers www.national.com/amplifiers Audio www.national.com/audio Clock and Timing www.national.com/timing Data Converters www.national.com/adc Interface www.national.com/interface LVDS www.national.com/lvds Power Management www.national.com/power Switching Regulators www.national.com/switchers LDOs www.national.com/ldo ...

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    ... Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should obtain the latest relevant information before placing orders and should verify that such information is current and complete. All products are sold subject to TI’ ...