-. ANALOG t W HighPerformance Digital-to-AnalogConverter DEVICES PRELIMINARY TECHNICAL DATA FEATURES 12 Bit Resolution . Input Register Included Small Module Package Programmable Output Ranges 0 to +70° C Monotonicity Low 8ppmfC Gain TC 2J1.sSettling Time OBS t OLE GENERAL DESCRIPTION The DACl132 is a 12 bit, high performance digital-to-analog converter packaged in a very compact 2" x 2" x 0.4" module. It comes complete with an input storage register and a fast settling output amplifier which can be jumper programmed to produce either of five output voltage ranges. Performance specifications include 2Jl.Ssettling time to 0.01 %, 8ppm/C gain temperatUre coefficient, :!:~LSB linearity error, and monotonicity from 0 to +70°C. OUTPUT CHARACTERISTICS The 12 binary-weighted current sources which form the basis of the digital-to-analog conversion process are directly controlled by the digital data stored in the input register. The combined output of these sources is applied to the internal op amp summing junction to produce a voltage output signal. By connecting jumpers between the proper module pins, various values of op amp feedback resistance and thus, output voltage ranges can be selected. The DACl132 combines the ADS 62 integrated circuit DIA with a TTL input register, an output amplifier, and a precision reference source to form a complete converter package. The laser trimmed ADS62 which consists of precision current switches, and a very stable thin film resistor network provides the DACl132 with excellent performance over temperatUre and makes possible its small module size. In order to produce bipolar outputs, the current input to the internal op amp is offset by ~ Full Scale. This offset current is generated bv the precision internal reference source and is applied to the op amp summing junction by means of a jumper connected betWeen appropriate module terminals. TE DIGITAL INPUT CHARACTERISTICS The TTLlDTL compatible storage register contained within the DAC1132 accepts either Binary or Offset Binary coded inputs. Digital data appearing at the converter's 12 input terminals will be strobed into the register whenever a positive going transition is applied to the STROBE input (pin 6). With the STROBE input held at either logic "0" or logic "1", the input data may be changed without affecting either the contents of the register or the output of the converter. The transfer characteristics of the DACl132 are such that a full scale digital input (111111111111) results in a positive full scale voltage output. t Note: this data sheet includes "Preliminary Technical Data" describing a new product. Though highly unlikely, it may be necessary to alter the specifications to reflect life data collected during the initial months of the product's use. Information furnished by Analog Devices is believed to ba 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 panies which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Route 1 Industrial Park; P.O. Box 280; Norwood, Mass. 02062 Tel: 617/329-4700 TWX: 710/394-6577 West Coast Tel: 213/595-1783 Mid-West Tel: 312/297-87"10 . ~""--=_.~~ -. ....- .. SPECIFICATIONS (typical @+25°C and rated supply voltages, unlessotherwise specified) DIGITAL OUTLINE DIMENSIONS AND PIN DESIGNATIONS Dimensionsshown in inches and (mm). 12 Bits RESOLUTION INPUTS OV ~ Logic "0" ~ 0.8V +2V ~ Logic "1" ~ +5V 1 Standard TTL Loadlbit 2 Standard TTL Loads 20ns (Min) 20ns (Min) 5ns Logic Levels Data Input Load Strobe Input Load Strobe Pulse Width . Data Setup Time Data Hold Time ---~ INPUT CODES Unipolar _.. Bipolar -OUTPUT RANGES f- Reference Voltage TEMPERATURE RANGE Operating POWER S.UPPLY SENSITIVITy3 Gain Offset (unipolar) Offset (bipolar) Reference AD1uSTMENTS (User Provided) Gain Offset o.41 MAX (10.4) 0.2MIN ~""2.01MAX f NOTE: Terminal pins installed only in shaded hole locations. Module weight: 1.6 ounces (45 grams) All pins are gold plated half-hard brass, (MIL-G-45204), 0.019" :to.OO1" (0.483 :to.025mm) dia. For plug-in mounting card order Board No. AC1506 @$30. 2.0p.s (3.0p.s Max) to 0.01 %T IY2LSB OLE I8.0ppm/C (I10ppm/C Max) of Reading I13p.V/C (I16p.V/C Max) I2.6ppm/C (I3.2ppm/C Max) I2.8ppm/C (I3.0ppm/C Max) of Full Scale I5ppm/C (I12ppm/C Max) 0 to +70°C -55°C to +lOO°C +15V I3% @ 32mA (37mA Max) -15V I3% @ 27mA (30mA Max) +5V I3% @ 140mA (150mA Max) POWER REQUIREMENTS 1 For a lOV i] ~ OBS Unipolar Offset Bipolar Offset2 Differential Nonlinearity t -1 Binary Offset Binary 0 to +5V @ lamA 0 to +10V @ 10mA I2.5V @ 10mA I5V @ lamA I10V @ 10mA OUTPUT IMPEDANCE SETTLING TIME LINEARITY ERROR TEMPERATURE COEFFICIENT Gain2 PRICE (1-9) 2.01 MAX (51.1) 8 TE BLOCK DIAGRAM BIT8 14 8 - 8 4 15 BIT9 16 BIT 10 BIT7 13 BIT6 12 BITS 11 17 BIT 11 18 LSB BIT410 BIT 3 9 4mV/V 4mV/V 4mV/V 2p.V/V 21 BIPOLAR OFFSET BIT28 (7mV/V Max) (7mV/V Max) (7mVN Max) (5IlV/V Max) 22 GAIN MSB 7 STROBE 8 ~ 24 +5V 3 +15V 2 ~+5V 28 ANALOG ~+15V 27 SUM JUNCT. -15V 1 ~-I5V KEY K 28 OFFSET ADJUST 0 GNO S IRLSB (Min) I10LSB $159 ADJ. 23 20V 10V 25 REF. OUT CUT '= 5.1k11 step. 2 These figures include the effects of Reference Voltage Temperature Drift. For :tl5V supplies only with +l5V and -l5V supplies tracking. Specifications subject to change without notice. 3 -2- '8 DIGITAL INPUT DATA All digital inputs to the DAC1132 are fully DTL/TTL compatible, The 12 data inputs (pins 7-18) each represent one standard TTL load and the STROBE (pin 6) represents two TTL loads, The converter uses Binary input code to produce unipolar outputs and Offset Binary code to produce bipolar outputs, The two 5krl. feedback resistors associated with the op amp of Figure 2 are used to determine the output voltage range. Serial and parallel combinations of these resistors yield three different resistance values. Table 1 shows the feedback connections used. to obtain the various output voltage ranges. Provided that certain timing requirements are met, data appearing at the converter's input terminals is loaded into the register by the positive-going edge of the strobe pulse, Figure 1 illustrates the required strobe timing, Unipolar Units :t2.5V :t5.0V :t10V Output Range Bipolar Units 0 to +5V Oto+lOV Pins jumpered Together Pin 23 To: Pin 26 To: 24 24 23 27 -- -- Table 1. Range Programming Table DATA MUST BE STABLE~ -.<5ns : 20ns MIN SETUP . I MIN ~ ~OLD I I 20ns MIN PULSE WIDTH ~ OBS : r, '1.5V I L 20ns INPUT-OUTPUT RELATIONSHIPS Table 2 and Table 3 list the analog outputs associated with various digital inputs for unipolar and bipolar units respectively. I :I Ii I l 25ns DIGIT AL INPUT NOMINAL VOLTAGE OUTPUT 40ns 0 to +IOV Range +4.9988V +0.0012V O.OOOOV +9.9976V +0.0024V O.OOOOV OLE Figure 1. Strobe Timing Diagram Note that the input data must be stable for at least 20ns before and 5ns after the pulse's leading edge. Note also that the strobe pulse must be a minimum of 20ns wide. In order to allow adequate time for the converter's analog output to settle between conversions, the strobe frequency should be limited to 500kHz. 8 0 to +5V Range OUTPUT CONNECTIONS Figure 2, below, shows the output configuration of the DAC1132 in simplified form. 23 20V RANGE 24 10V RANGE 25 REFERENCE OUT 26 ANALOG OUTPUT Offset Binary Code 111111111111 100000000001 100000000000 000000000000 Relationships NOMINAL VOLTAGE OUTPUT :t2.5V Range 0 0 TO -2mA FROM I.C. DIA TE Table 2. Unipolar Input-Output DIGIT AL INPUT 21 BIPOLAR OFFSET 995011 Binary Code 111111111111 000000000001 000000000000 :t5V Range :tIOV Range t-9.9951V +2.4988V +4.9976V 0.0012V 0.0048V 0.0024V O.OOOOV O.OOOOV O.OOOOV -10.0000V -2.5000V -5.0000V 27 SUMMING JUNCT. 28 OFFSET ADJUST Table 3. Bipolar Input-Output Relationships 2.2M GAIN, AND OFFSET ADJUSTMENTS The gain and offset adjustments are made with two external potentiometers which the user supplies. With certain digital inputs applied, these potentiometers are adjusted until the desired output voltage is obtained. The voltmeter used to measure the output must be capable of clear and stable resolution of 1/10LSB in the region of zero and full scale. The adjustment procedure, described below, should be carefully followed to assure optimum converter performance. Figure 2. Output Circuit Block Diagram External jumper connections determine whether the DAC1132 will be a unipolar or a bipolar device. Figures 3a and 3b below show the proper connections for both configurations. 0 BIPOLAR OFFSET 0 210 BIPOLAR OFFSET 210- 0 0 0 0 0 0 REF. OUT. 250 REF. OUT. 250 0 8 CW 28 0 0 20kl1 20 TURN OFFSET ADJUST GAIN ADJ. 22 +15V +15V 0 OFFSET ADJUST The proper connection for the offset potentiometer was shown in Figures 3a and 3b. The gain potentiometer should be connected as shown below in Figure 4. 0 OFFSET ADJUST CW 28 0 20kn 20 TURN OFFSET ADJUST CW 0 10011 20 TURN GAIN ADJUST REF. OUT. 25 0 a. Unipolar -15V b. Bipolar -15V Figure 4. Gain Adjustment Figure 3. Unipolar/Bipolar Output Connection -3-- --- -- - Connection For unipolar units apply a digital input of 000000000000 and adjust the offset potentiometer until an output of OV :tl/l0LSB is obtained. The output voltage range is programmed by means of jumpers which the user installs as shown in Figure 7. For bipolar units apply a digital input of 000000000000 and adjust the offset potentiometer until the negative full scale output shown in Table 3 is obtained within :tl/l0LSB. Once the appropriate offset adjustment has been made, apply a digital input of 111111111111. Adjust the gain potentiometer until the positive full scale output shown in Table 2 or Table 3 is obtained within :tl/l0LSB. I 1 I :: I I .,. ,... ..... I I <3 @@ 8 I I I -z @I 0 I 0 I ,... @ .::;: N u « +5V SUPPLY <15V SUPPLY : $i POWER SUPPLY AND GROUNDING CONNECTIONS The proper power supply and grounding connections are shown below in Figure 5. KO I :2: +5V 2 OBS COM J OUTPUT VOLTAGE RANGE 5 0 0 to +10V 0 to +5V :t2.5V :t5V :tlOV 0 OLE Figure 5. Power Supply and Grounding Connections Capacitors have been added within the DAC1132 to bypass the :t15V and +5V power inputs. Under normal circumstances, no external bypass capacitors are needed. REFERENCE OUTPUT The +10V reference output (pin 25) is used to set the converter's gain as shown in Figure 4 and to provide the offset for bipolar devices as shown in Figure 3. It may also be used to provide a reference voltage for otner circuits in the user's system provided that the output current is limited. No more than 1.5 mA should be drawn from bipolar devices and no more than 2.5mA should be drawn from unipolar devices. Excessive current drain will degrade the converter's analog output and could damage the internal reference source. Figure 7. AC 1506 Range Programming r n DAC1132 TE The pin connections are as shown below in Table 4. Pin A B C D E F H J THE AC1506 MOUNTING CARD The AC1506 mounting card is available to assist in the application ofthe DAC1132. This 4.5" x 3.0" printed circuit card, shown below in Figure 6, has sockets which allow a DAC1132 to be plugged directly onto it. It includes the necessary gain, and offset adjustment potentiometers and it mates with a Cinch 250-22-30-170 (or equivalent) edge connector which is supplied with every card. 4.500 JUMPER CONNECTION A-C A - C, F - H D - E, A - C, F - H D E,A C A - B, D - E K L M Designation MSB Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 7 Bit 8 Bit 9 Bit 10 Bit 11 Pin N P R S T U V W X Y Z Designanon Bit 12 N.C. N.C. Ground Ref. Out. Analog Out. Strobe +5V +15V -15V Ground 8 Table 4. AC1506 Pin Designations -i. uj ::J Z 0 w .,' (114.301 ~ Iz a: B. ~ 3.000 (76.201 8 DIMENSIONS SHOWN ARE IN INCHES AND (MMI. Figure 6. AC1506 Outline Drawing -4-