lm12l458civf National Semiconductor Corporation, lm12l458civf Datasheet
lm12l458civf
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lm12l458civf Summary of contents
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... The LM12L458 includes a direct memory access (DMA) interface for high-speed conversion data transfer. Additional applications information can be found in applica- tions notes AN-906, AN-947 and AN-949. TRI-STATE ® registered trademark of National Semiconductor Corporation. © 2006 National Semiconductor Corporation Key Specifications ( MHz) CLK n Resolution ...
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Connection Diagram *Pin names apply to the obsolete LM12L454, shown for reference only. Order Number LM12L458CIV See NS Package Number V44A Functional Diagram Ordering Information Guaranteed Clock Freq 6 MHz www.national.com LM12L458 Guaranteed Linearity Error (max) Part ...
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Absolute Maximum Ratings (Notes Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage (V + and Voltage at Input and Output Pins, except ...
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Converter Characteristics The following specifications apply for V 6.0 MHz 25Ω, source impedance for V S age, and minimum acquisition time unless otherwise specified. Boldface limits apply for T limits 25˚C. (Notes 6, 7, ...
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DC Characteristics The following specifications apply for V tion time unless otherwise specified. Boldface limits apply for Symbol Parameter Supply Current Supply Current A A Stand-By ...
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Digital Timing Characteristics The following specifications apply for V unless otherwise specified. Boldface limits apply for T Symbol (See Figures 10, 11, 12 Address Valid to ALE Low Set- Time CS or Address Valid to ALE ...
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Electrical Characteristics Note and V + must be connected together to the same power supply voltage and bypassed with separate capacitors at each conversion/comparison accuracy. Note 8: Accuracy is guaranteed when operating at f ...
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Input and Reference Range − V REF REF+ REF− − IN+ IN− GND ≤ V ≤ IN+ A GND ≤ V ≤ IN− A FIGURE 2. The General ...
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Input and Reference Range FIGURE 4. The General Case of the V FIGURE 5. The Specific Case of the V (Continued) Operating Range REF Operating Range for V REF 9 01171107 01171108 + = 3.3V A www.national.com ...
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Transfer Characteristic and Static Errors FIGURE 7. Simplified Error Curve vs. Output Code without Auto-Calibration or Auto-Zero Cycles www.national.com FIGURE 6. Transfer Characteristic 10 01171109 01171110 ...
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Transfer Characteristic and Static Errors FIGURE 8. Simplified Error Curve vs. Output Code after Auto-Calibration Cycle (Continued) FIGURE 9. Offset or Zero Error Voltage 11 01171111 01171112 www.national.com ...
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Typical Performance Characteristics calibration with +3.3V The performance for 8-bit + sign and “watchdog” modes is equal to or better than shown. (Note 9) Linearity Error Change vs. Clock Frequency Linearity ...
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Typical Performance Characteristics auto-calibration with +3.3V specified. The performance for 8-bit + sign and “watchdog” modes is equal to or better than shown. (Note 9) (Continued) Full-Scale Error Change vs. Reference ...
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Typical Performance Characteristics auto-calibration with +3.3V specified. The performance for 8-bit + sign and “watchdog” modes is equal to or better than shown. (Note 9) (Continued) Analog Supply Current vs. Temperature ...
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Timing Diagrams ns 100 pF for the INT, DMARQ, D0–D15 L outputs Address valid to ALE low set-up time Address valid to ALE ...
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Timing Diagrams outputs. (Continued pulse width 9: RD high to next low 11: WR pulse width 13: WR high to next low 14: Data valid to WR ...
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Pin Descriptions Analog and digital supply voltage pins. The A D LM12L458’s supply voltage operating range is +3.0V to +5.5V. Accuracy is guaranteed only and V + are connected to the same power ...
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Functional Description The LM12L458 is a multi-functional Data Acquisition System that includes a fully differential 12-bit-plus-sign self- calibrating analog-to-digital converter (ADC) with a two’s- complement output format, an 8-channel analog multiplexer, a first-in-first-out (FIFO) register that can store 32 ...
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Internal User-Programmable Registers (Continued) limit #2, its sign, and an indicator that shows that an interrupt can be generated if the input signal is greater or less than the programmed limit. Instruction RAM “00” Bit 0 is the LOOP ...
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www.national.com 20 ...
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Purpose Instruction RAM (RAM Pointer = 00 Instruction ...
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Internal User-Programmable Registers (Continued kΩ and MHz. Round the result to the next S CLK higher integer value greater than 15 advisable to lower the source impedance by ...
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Internal User-Programmable Registers (Continued) full calibration mode because eight samples of the offset voltage are taken, averaged, and used to create a correction value. Bit 7 is used to program the SYNC pin (29) to operate as either an ...
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Internal User-Programmable Registers (Continued) is equal to the value stored in Bits 8–10, an internal interrupt is generated and appears in Bit 1 of the Interrupt Status register. If Bit 1 of the Interrupt Enable register is set to ...
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Other Registers and Functions (Continued) conversion result from the FIFO. Therefore, the DMA con- troller must be able to repeatedly access two constant ad- dresses when transferring data from the LM12L458 to the host system. 4.0 FIFO The result ...
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Sequencer (Continued) FIGURE 15. Sequencer Logic Flow Chart (IP = Instruction Pointer) www.national.com 01171122 26 ...
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Analog Considerations 6.1 REFERENCE VOLTAGE The difference in the voltages applied to the V V defines the analog input voltage span (the difference REF− between the voltages applied between two multiplexer inputs or the voltage applied to one of ...
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Common Application Problems (Continued range. This could happen in normal operation if the A amplifier use supply voltages outside of the range of the LM12L458 supply rails. This could also happen upon power up if the amplifier ...
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Physical Dimensions inches (millimeters) unless otherwise noted National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and ...