LTC1840 LINER [Linear Technology], LTC1840 Datasheet
LTC1840
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LTC1840 Summary of contents
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... R SENSE2 V IN 0.05 RUN/SS SENSE LTC1771 I PGATE MODE 10k FB2 GND 220pF 100pF LTC1840 Dual Fan Controller with 2-Wire Interface and SMBus compat VIN1 3. FB1A 10k FAN 75k + Si6447DQ C OUT1 TACH 150 F R OUT ...
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... A0, A1 ............................................. –0 DACOUTB ............................. DACOUTA All other pins ................................................. –0 Operating Temperature LTC1840C ............................................... LTC1840I .............................................– Storage Temperature Range ..................– 125 C Lead Temperature (Soldering, 10 sec).................. 300 C ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER ...
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... Measured on Rising Edge and 0V GND Shorted to GND (Note 2) (Note 2) (Note 2) (Note 2) (Note 2) (Note 2) (Note 2) (Note 2) (Note 2) (Note 2) Note 2: Guaranteed by design not subject to test. LTC1840 MIN TYP MAX UNITS 1 0.4 V 0 0.3V ...
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... LTC1840 W U TYPICAL PERFOR A CE CHARACTERISTICS Supply Current vs Supply Voltage 550 500 450 400 2.5 3.5 4.5 5.5 6.5 V (V) CC 1840 G01 DACOUT DACOUT 120 100 (V) DACOUT 1840 G04 I AC Supply Rejection at ...
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... SDA (Pin 2): Serial Data Input. This is a bidirectional data pin which normally has an external pull-up resistor or current source and can be pulled down by the open drain device on the LTC1840 or by external devices. The master controls SDA during addressing, the writing of data, and read acknowledgment, while the LTC1840 controls SDA when data is being read back and during write acknowl- edgment ...
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... BLAST pin or by the serial access timer enabled and the LTC1840 is not accessed for about 1.5 minutes. This pin will maintain the programmed current to a very tight tolerance from as low as 1 ...
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... Data Transfer Timing for Write Commands In order to help assure that bad data is not written into the LTC1840, data from a write command is only stored after a valid acknowledge has been performed. The part will detect that SDA is low on the rising edge of SCL that marks ...
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... For the A0 and A1 lines, L refers to a grounded pin pin shorted to V and connect. The pin voltage CC will be set to approximately V /2 when not connected. CC Bits B7, B6 and B5 of the address are hardwired to 111. Table 2. LTC1840 Register Address and Contents Register Register Name Address (R/ ...
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... SDA low. Next, send the LTC1840 the value indicating the DACA current; writing the SDA data stream 10000000 sets the DAC to sink 50 A. The LTC1840 will then acknowledge a third time by pulling SDA low for the next SCL cycle. Then the data will be written into the ...
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... A = 69.8k, and the bottom resistor is 69.8k/3 = 23.2k. See Figure 1. If the feedback pin voltage of a regulator is lower than the 1.1V compliance voltage of either of the LTC1840’s cur- rent output DACs, the resistor from the regulator output to the feedback pin can be divided into two resistors, giving the DAC more room to operate ...
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... Plastic SSOP (Narrow .150 Inch) (Reference LTC DWG # 05-08-1641) 0.229 – 0.244 (5.817 – 6.198) 0.015 0.004 45 0.053 – 0.068 (0.38 0.10) (1.351 – 1.727) 0 – 8 TYP 0.008 – 0.012 (0.203 – 0.305) LTC1840 V OUT (5V TO 12V) R3 LTC1840* 69.8k I DAC I DACOUTA 1. 15(14) DACOUTB 10k REGULATOR 0.8V FB 1840 F02 ...
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... LTC1840 U TYPICAL APPLICATIO 12V L1 = SUMIDA CDRH125-15OMC 10k PANASONIC EEV-FC1C471P IN OUT R1 METAL FILM TN0205A 3.3V 0.1 F LTC1840 LTC1840 1 16 SCL V SCL SDA SDA I DACOUTA 3 14 10k DACOUTB 130 4 13 SYSTEM FAULT A0 BLAST NC RESET LED1 5 12 FAULT TACHB 3. GPIO1 ...