LTC2704-14 Linear Technology Corporation, LTC2704-14 Datasheet
LTC2704-14
Related parts for LTC2704-14
LTC2704-14 Summary of contents
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... Voltage Output SoftSpan DESCRIPTIO ® The LTC 2704-16/LTC2704-14/LTC2704-12 are serial in- put, 12-, 14- or 16-bit, voltage output SoftSpan™ DACs that operate from logic and ±5V to ±15V analog supplies. SoftSpan offers six output spans—two unipolar and four bipolar—fully programmable through the 3-wire SPI serial interface ...
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... AGNDC REF2 22 23 REFM2 GW PACKAGE 44-LEAD PLASTIC SSOP = 125°C, θ = 80°C/W JA http://www.linear.com/leadfree/ = 25°C, A LTC2704-14 LTC2704-16 MIN TYP MAX MIN TYP ±1 ±1 ±1 ±1 ±2 ±1 ±5 ±4 ±2 ±2 ±80 ±200 ±80 ± ...
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... Shorted to V –36 OUT ● 2.2 3 ● 2.0 2.8 1000 CONDITIONS + – = ±15V Span (Note LTC2704 = 25°C, A LTC2704-14 LTC2704-16 MAX MIN TYP MAX MIN TYP ±2 ±2 ±2 ±2 ±1 ±0.5 ±2 ±2 ±2 ±2.5 ±0.013 ±0.05 ±0.025 ± ...
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... LTC2704 ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are – 15V –15V 5V, REF1 = REF2 = 5V, AGND = AGNDx = REFG1 = REFG2 = GND = 0V SYMBOL PARAMETER AC Performance (Note 4) Glitch Impulse Crosstalk Digital Feedthrough ...
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... MAX device. Differential Nonlinearity (DNL) 1 – = ±15V 0 REF ±10V RANGE 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1.0 0 16384 32768 49152 CODE LTC2704 MIN TYP ● 15 ● ● ● ● 9 ● 9 ● 15 ● 15 ● 12 ● 0 ● 12 ● 12 ● ● 90 ● 20 ● ...
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... LTC2704 W U TYPICAL PERFOR A CE CHARACTERISTICS LTC2704-16 INL vs Temperature 1 – = ±15V 0.8 REF ±10V RANGE 0.6 0.4 MAX 0.2 0 MIN –0.2 –0.4 –O.6 –0.8 –1.0 –50 – – TEMPERATURE (°C) 2704 G04 Bipolar Zero vs Temperature – = ±15V REF 6 ±10V RANGE ...
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... REF ±10V RANGE 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1.0 0 512 1536 1024 2048 CODE LTC2704-16/LTC2704-14/LTC2704-12 Positive Slew 5V/DIV 2704 G13 – = ±15V 2.5µs/DIV REF ±10V RANGE 20V STEP Differential Nonlinearity (DNL) 1 0.8 V ±10V RANGE 0.6 0.4 0.2 0 – ...
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... LTC2704 W U TYPICAL PERFOR A CE CHARACTERISTICS LTC2704-16/LTC2704-14/LTC2704-12 0.1Hz to 10Hz Noise 1µV/DIV – = ±15V 1s/DIV REF RANGE CODE = CTIO S – V (Pins 1, 8, 15, 22, 31, 36): Analog Negative Supply, Typically –15V. –4.5V to –16.5V Range. REFG1 (Pin 2): Reference 1 Ground. High impedance input, does not carry supply currents ...
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... Analog Positive Supply for DACs A DND B. 1 Typically 15V. 4.5V to 16.5V Range. Can be different from + REF1 (Pin 43): DAC A and DAC B Reference Input. REFM1 (Pin 44): Reference 1 Inverting Amp Output. The gain from REF1 to REFM1 is –1. Can swing to within 0.5V + – of the analog supplies LTC2704 2704f 9 ...
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... LTC2704 W BLOCK DIAGRA REF1 43 VOSB 40 C1B 39 RFBB 37 OUTB 38 DAC B AGNDB + 41 – VOSA 4 C1A 5 RFBA 7 OUTA 6 DAC A AGNDA + 3 – REFM1 44 REFG1 2 CS/ DIAGRA SCK SDI CS/LD LDAC Hi-Z SRO 10 32 – V AGND 1,8,15,22,31,36 – – COMMAND INPUT DAC DECODE ...
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... The minimum (24-bit wide) load- ing sequence required for the LTC2704 is a 4-bit com- mand word ( C0), followed by a 4-bit address word ( A0) and 16 data (span or code) bits, MSB first ...
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... LTC2704 U OPERATIO OUTPUT RANGES The LTC2704 is a quad DAC with software-programmable output ranges. SoftSpan provides two unipolar output ranges ( and 0V to 10V), and four bipolar ranges (±2.5V, ±5V, ±10V and – 2.5V to 7.5V). These ranges are obtained when an external precision 5V reference and analog supplies of ± ...
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... U OPERATIO LTC2704 2704f 13 ...
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... LTC2704 U OPERATIO 14 2704f ...
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... Data Out on SRO = 0000 0000 0000 0100 Verifies that B1-Range of DAC C set to Bipolar ±2.5V Range. CS/LD↑ h) CS/LD↓ Clock SDI = 0000 0000 0100 0100 xxxx xxxx xxxx xxxx i) CS/LD↑ Update DAC C B1 into B2 for both Code and Range j) Alternatively steps h and i could be replaced with LDAC . LTC2704 2704f 15 ...
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... If not used, they should be shorted to their respective signal grounds, AGNDx. POWER-ON RESET AND CLEAR When power is first applied to the LTC2704, all DACs power- unipolar mode ( 0000). All internal DAC registers are reset to 0 and the DAC outputs are zero volts ...
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... When in doubt, use a single solid ground plane rather than separate planes. The LTC2704 does allow the ground potential of the DACs to vary by ±300mV with respect to analog ground, allow- ing compensation for ground return resistance. ...
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... U APPLICATIO S I FOR ATIO Voltage Output/Feedback and Compensation The LTC2704 provides separate voltage output and feed- back pins for each DAC. This allows compensation for resistance between the output and load current boosting stage such as an LT1970 may be inserted with- out affecting accuracy ...
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... DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.152mm (0.006") PER SIDE ** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.254mm (0.010") PER SIDE LTC2704 17.73 – 17.93* (.698 – .706) 10.11 – 10.55 (.398 – .415) 22 2.286 – 2.388 (.090 – ...
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... DD 12 INTERFACE SRO SRO 13 10k SCK SCK 14 1k CLR CLR 35 RFLAG 2 1 REFG1 GND1 43 2 REF1 REF1 REF1 REFM1 REFM1 LTC2704 21 1 REFG2 GND2 24 REF2 2 REF2 REF2 REFM2 REFM2 BAT54S REF ...