LTC1657 LINER [Linear Technology], LTC1657 Datasheet
LTC1657
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LTC1657 Summary of contents
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... SSOP or PDIP package. It includes a rail-to-rail output buffer amplifier, an internal 2.048V reference and a double buffered parallel digital interface. The LTC1657 operates from a 4.5V to 5.5V supply. It has a separate reference input pin that can be driven by an external reference. The full-scale output can times the reference voltage depending on how the X1/X2 pin is connected ...
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... X1/X2 ....................................................... – 0. REFOUT ............................ – 0. OUT Operating Temperature Range LTC1657C ............................................. LTC1657I ........................................ – Maximum Junction Temperature .......................... 125 C Storage Temperature Range ................ – 150 C Lead Temperature (Soldering, 10 sec)................. 300 C ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T REFLO tied to GND, X1/X2 tied to GND, unless otherwise noted. ...
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... Measured 100 A OUT REFOUT Shorted to GND (Note 6) See Applications Information X1/X2 Tied to V OUT X1/X2 Tied to GND Note 4: Digital inputs Note 5: DAC switched between all 1s and all 0s. Note 6: Guaranteed by design. Not subject to test. LTC1657 MIN TYP MAX UNITS 0.3 0 ...
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... LTC1657 W U TYPICAL PERFOR A CE CHARACTERISTICS Differential Nonlinearity 1.0 0.8 0.6 0.4 0.2 0.0 –0.2 –0.4 –0.6 –0.8 –1.0 0 16384 32768 49152 65535 DIGITAL INPUT CODE 1657 G01 Minimum Output Voltage vs Output Sink Current 1.2 CODE ALL 0’S V 1LSB OUT 1.0 125 C 0.8 0 0.4 – OUTPUT SINK CURRENT (mA) ...
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... LDAC (Pin 28): Load DAC (Asynchronous Active Low). Used to asynchronously transfer the contents of the input registers to the DAC register which updates the output voltage. If held low, the DAC register loads data from the input registers which will immediately update V LTC1657 CC , OUT . OUT ...
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... LTC1657 U DIGITAL INTERFACE TRUTH TABLE CLR CSMSB CSLSB TIMING DIAGRAM CSLSB CSMSB t CWS WR LDAC DATA 6 WR LDAC FUNCTION X X Clears input and DAC registers to zero ...
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... Least Significant Bit (LSB): One LSB is the ideal voltage difference between two successive codes. n LSB = (V – V )/(2 – Nominal LSBs: LTC1657 LSB = 4.096V/65535 = 62.5 V DAC Transfer Characteristic: REFHI REFLO – • CODE OUT 65536 for X1/X2 connected to V OUT ...
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... CLR pin function). Reference The LTC1657 includes an internal 2.048V reference, giv- ing the LTC1657 a full-scale range of 4.096V in the gain- of-2 configuration. The onboard reference in the LTC1657 is not internally connected to the DAC’s reference resistor string but is provided on an adjacent pin for flexibility. ...
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... Offset and linearity are defined and tested over the region of the DAC transfer function where no output limiting can occur OUTPUT REF CC VOLTAGE 0 32768 65535 INPUT CODE (a) LTC1657 / and the DAC full-scale CC REF CC as shown in Figure 1c. No full-scale limiting CC is less than (V – FSE)/2. REF ...
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... This circuit shows a digitally programmable current source from an external voltage source using an external op amp, an LT1218 and an NPN transistor (2N3440). Any digital word from 0 to 65535 is loaded into the LTC1657 and its output correspondingly swings from 0V to 4.096V. This voltage will be forced across the resistor R ...
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... MIN 0.125 0.005 0.100 (3.175) (2.54) MIN (0.127) BSC MIN LTC1657 0.386 – 0.393* (9.804 – 9.982) (0.838 1615 0.150 – 0.157** (3.810 – 3.988 ...
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... V CC DATA (0:15) 2 CSLSB 3 CSMSB P LTC1657 LDAC 27 CLR X1/X2 REFLO GND shown in the configuration, the output of LTC1657 is amplified by 8 for an output swing 32.768V convenient 0.5mV/LSB. A Higher Voltage Output DAC 5V 36V OUT 6 LT1218 2 – ...