LTC2754 LINER [Linear Technology], LTC2754 Datasheet
LTC2754
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LTC2754 Summary of contents
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... They operate from a single supply and are guar- anteed monotonic over temperature. The LTC2754A-16 provides full 16-bit performance (±1LSB INL and DNL, max) over temperature without any adjustments. These SoftSpan™ ...
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... V to GND .................................................. –0. Digital Inputs and Outputs to GND ................ –0. Operating Temperature Range LTC2754C ................................................ 0°C to 70°C LTC2754I..............................................–40°C to 85°C Maximum Junction Temperature........................... 150°C Storage Temperature Range ...................–65°C to 150°C ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL ...
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... REF RMS Code = Full Scale, –3dB Range ±10V, 10kHz REF Sine Wave (Note 8) (Note 9) Multiplying (Note 10 OUT1 LTC2754 denotes the ● = 25°C. A LTC2754B-16 LTC2754A-16 MIN TYP MAX MIN TYP MAX ±1 ±0.2 ±2 ±0.4 ±20 ±2 ± ...
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... LTC2754 ELECTRICAL CHARACTERISTICS specifi cations which apply over the full operating temperature range, otherwise specifi cations are at T SYMBOL PARAMETER Power Supply V Supply Voltage DD I Supply Current Digital Inputs V Digital Input High Voltage IH V Digital Input Low Voltage ...
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... Differential Nonlinearity (DNL REF ±10V RANGE 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1.0 32768 0 16384 49152 CODE LTC2754 MIN TYP MAX ● 5 ● 5 ● 26 ● 60 ● 20 ● 70 ● 60 ● 25 OUTB 1kHz sine wave. Crosstalk REFA RMS at 1kHz range. DAC code = FS. Output RMS = √ ...
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... LTC2754 TYPICAL PERFORMANCE CHARACTERISTICS LTC2754-16 DNL vs Temperature 1 0 REF ±10V RANGE 0.6 0.4 0.2 +DNL 0.0 –DNL –0.2 –0.4 –0.6 –0.8 –1.0 –40 – TEMPERATURE (°C) 2754 G04 INL vs V REF 1 0.8 ±5V RANGE 0.6 0.4 +INL 0.2 0.0 –INL –0.2 –0.4 –0.6 –0.8 –1.0 –10 –8 – ...
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... V OUT 5mV/DIV 500ns/DIV REF 5V RANGE LT1468 OUTPUT AMPLIFIER C = 27pF FEEDBACK RISING MAJOR CARRY TRANSITION. FALLING TRANSITION IS SIMILAR OR BETTER LTC2754 T = 25°C, unless otherwise noted 1024 2048 3072 4095 CODE 2754 G12 Supply Current vs Clock Frequency 100 ...
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... Nominal adjustment range is ±512 LSB INA (LTC2754-16) for a voltage input range of ±V for a 5V reference input). Tie to ground if not used. R (Pin 15): Center Tap Point for Reference Amplifi er COMD Inverting Resistors ...
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... OSADJD pin can be used to null unipolar offset or bipolar zero error. The offset voltage delta is inverted and attenuated such that a 5V control voltage applied to V OSADJD -512 LSB (LTC2754-16) in any output range (assumes a 5V reference voltage Tie to ground if not used. IND V (Pin 21): DAC C Offset Adjust Pin ...
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... V OSADJA pin can be used to null unipolar offset or bipolar zero error. The offset-voltage delta is inverted and attenuated such that a 5V control voltage applied to V –512 LSB (LTC2754-16) in any output range (assumes a 5V reference voltage at R (i.e., ±5V RINB I (Pin 48): DAC A Current Output. This pin is a virtual ...
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... SPAN REGISTERS 3 DAC REG INPUT REG INPUT REG POWER-ON RESET CONTROL AND READBACK LOGIC RFLAG CLR CS/ LTC2754 and R fl oating). INA COMA to R INA COMA to the negative input of external COMA R 39 INB 2.56M 40 GE 20k ADJB R 41 COMB ...
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... Manual Span Confi guration Multiple output ranges are not needed in some applica- tions. To confi gure the LTC2754 to operate in a single span without additional operational overhead, tie the M-SPAN pin directly The active output range for all four ...
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... OPERATION Input and DAC Registers The LTC2754 has 5 internal registers for each DAC, a total of 20 registers (see Block Diagram). Each DAC channel has two sets of double-buffered registers—one set for the code data, and one for the output range of the DAC—plus one readback register ...
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... All DACs (Note 1) Codes not shown are reserved–do not use. × = Don’t Care. Note 1. If readback is taken using the All DACs address, the LTC2754 defaults to DAC A. 14 READBACK POINTER– CURRENT INPUT WORD W Set by Previous Command Set by Previous Command ...
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... Data Out on SRO = 0000 0000 0000 0100 Verifi es that Input register- range of DAC C set to Bipolar ±2.5V Range. CS/LD↑ f) CS/LD↓ Clock SDI = 0000 0000 0100 0100 xxxx xxxx xxxx xxxx g) CS/LD↑ Update DAC C for both Code and Range h) Alternatively steps f and g could be replaced with LDAC . LTC2754 2754f 15 ...
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... DACs. Many systems require compensation for overall system offset. This may be an order of magnitude or more greater than the offset of the LTC2754, which is so low dominated by external output amplifi er errors even when using the most precise op amps. The offset adjust pins V OSADJX unipolar offset or bipolar zero error ...
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... OPERATION LTC2754 2754f 17 ...
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... LTC2754 OPERATION 18 2754f ...
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... SRO INPUT DATA REGISTER DAC A WRITE DATA WRITE DATA DAC C DAC D READ READ INPUT DATA INPUT DATA REGISTER DAC B REGISTER DAC C Figure 4. Rolling Readback LTC2754 ... UPDATE ALL DACs READ READ INPUT DATA DAC DATA REGISTER DAC D REGISTER DAC A 2754 F04 2754f 19 ...
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... A1 • A2 • VOL1 A VOL1 V (mV) 0 OS2 I (mV (V/V) 0 VOL2 Table 6. Partial List of LTC Precision Amplifi ers Recommended for Use with the LTC2754 with Relevant Specifi cations AMPLIFIER μV nA LT1001 25 2 LT1097 50 0.35 LT1112 (Dual) 60 0.25 LT1124 (Dual) ...
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... DAC settling time and op amp selection. Precision Voltage Reference Considerations Much in the same way selecting an operational amplifi er for use with the LTC2754 is critical to the performance of the system, selecting a precision voltage reference also requires due diligence. The output voltage of the LTC2754 is directly affected by the voltage reference ...
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... Figure 5). This preserves the excellent accuracy (1LSB INL and DNL) of the LTC2754-16. Layout Figures and 9 show the layout for the LTC2754 evaluation board, DC1546. This shows how to route the digital signals around the device without interfering with the reference and output op amps. Complete demo board documentation is available in the DC1546 “ ...
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... BARRIER DIODE LTC2754- INA OUT1A 52 DAC OUT2A DAC B DAC C DAC D 2754 F05 from GND with a Force/Sense Amplifi er. OUT2 LTC2754 2 – 6 LT1001 ZETEX* BAT54S 2 3 FBA 15pF 2 – 1/2 LT1469 3 + OSADJA – + – + – ...
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... LTC2754 APPLICATIONS INFORMATION Figure 6. LTC2754 Evaluation Board DC1546. Layer 1, Top Layer (Component Side) Figure 7. LTC2754 Evaluation Board DC1546. Layer 2, GND Plane 24 2754 F06 2754 F07 2754f ...
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... APPLICATIONS INFORMATION Figure 8. LTC2754 Evaluation Board DC1546. Layer 3, Power Traces Figure 9. LTC2754 Evaluation Board DC1546. Layer 4, Bottom Layer (Solder Side) LTC2754 2754 F08 2754 F09 2754f 25 ...
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... 0.1μ INB RCOMB INA 30 CLR 31 RFLAG 5 CS/LD 6 SDI 7 SCK 8 SRO 36 LDAC LTC2754 32 M-SPAN GND GND GND GND SROGND R ADJA ADJB ADJC ADJD INC LT1991s 5V ...
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... DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.20mm ON ANY SIDE, IF PRESENT 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE LTC2754 5.50 REF (2 SIDES 0.115 TYP ...
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... LTC2754 RELATED PARTS PART NUMBER DESCRIPTION LT1027 Precision Reference LT1236A-5 Precision Reference LT1468 16-Bit Accurate Op-Amp LT1469 Dual 16-Bit Accurate Op-Amp LTC1588/LTC1589/ Serial 12-/14-/16-Bit I OUT LTC1592 LTC1591/LTC1597 Parallel 14-/16-Bit I Single DAC OUT LTC2704 Serial 12-/14-/16-Bit V OUT LTC2751 Parallel 12-/14-/16-Bit I OUT Single DAC ...