LM3814MX-1.0 National Semiconductor, LM3814MX-1.0 Datasheet
LM3814MX-1.0
Specifications of LM3814MX-1.0
Related parts for LM3814MX-1.0
LM3814MX-1.0 Summary of contents
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... Ultra low insertion loss (typically 0.004Ω 5.25V supply range Connection Diagrams Top View LM3814 for High-Side Sensing © 2005 National Semiconductor Corporation ± 3.5% accuracy at room temperature (includes n accuracy of the internal sense element) (LM3814-1.0, LM3815-1.0) n Low quiescent current in shutdown mode (typically 2.5 µ ...
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... Ordering Information # Order No. Sense Range ± LM3814M-1.0 1A ± LM3814MX-1.0 1A ± LM3814M-7.0 7A ± LM3814MX-7.0 7A ± LM3815M-1.0 1A ± LM3815MX-1.0 1A ± LM3815M-7.0 7A ± LM3815MX-7 Suffix M indicates that the part is available in Surface Mount package. Suffix X indicates that the part is available in 2.5k units on Tape and Reel. ...
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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Absolute Maximum Supply Voltage Power Dissipation ESD Susceptibility (Note 3) Sense Current (peak, for 200 msec) (Note 4) Sink Current for PWM pin ...
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Electrical Characteristics Common Device Parameters Unless otherwise specified 5.0V for the following specifications. Supply bypass capacitor is 1µF and filter capacitor is DD 0.1µF. Symbol Parameter V Logic Low Level for PWM OL P Insertion Loss I Note ...
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Typical Performance Characteristics 0.1µF. (Continued) PWM Frequency vs Supply Voltage Operating Current vs Supply Voltage Operating Current vs Temperature Supply bypass capacitor is 0.1µF and filter capacitor is PWM Frequency vs Temperature 10101314 Shutdown Current vs Supply Voltage 10101318 Shutdown ...
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Typical Performance Characteristics 0.1µF. (Continued) Current vs Duty Cycle Accuracy vs Temperature (LM3814-1.0 and LM3815-1.0) Error vs Current (LM3814-1.0 and LM3815-1.0) (Note 10) Note 10: These curves represent a statistical average such that the noise is insignificant. www.national.com Supply bypass ...
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Typical Application Circuits In the application circuits, the 0.1µF ceramic capacitor between pins 1 and 8 is used for bypassing, and the 0.1µF ceramic capacitor between pins 3 and 4 is used for filter- ing. Shutdown (SD) is tied to ...
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Typical Application Circuits is used for bypassing, and the 0.1µF ceramic capacitor between pins 3 and 4 is used for filtering. Shutdown (SD) is tied to V through a 10kΩ resistor. (Continued) DD FIGURE 3. Paralleling LM3814 for Higher Load ...
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Typical Application Circuits is used for bypassing, and the 0.1µF ceramic capacitor between pins 3 and 4 is used for filtering. Shutdown (SD) is tied to V through a 10kΩ resistor. (Continued) DD FIGURE 4. High Voltage Operation — V ...
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Product Operation The current is sampled by the delta-sigma modulator, as illustrated in Figure 6. The pulse density output of the delta- sigma modulator is digitally filtered. The digital output is then compared to the output of a digital ramp ...
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PWM Output and Current Accuracy OFFSET The PWM output is quantized to 128 levels. Therefore, the duty cycle can change only in increments of 1/128. There is a one-half (0.5) quantization cycle delay in the output of the PWM circuitry. ...
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Look-Up Tables The following tables show how to convert the duty cycle of the PWM output to a current value, and vice versa. The TABLE 1. CURRENT TO DUTY CYCLE CONVERSION TABLE Sense Current (Amps)* 1.00 0.95 0.90 0.85 0.80 ...
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TABLE 2. DUTY CYCLE TO CURRENT CONVERSION TABLE Duty Cycle Sense Current (%) 95.5 92.5 90.0 87.5 85.0 82.5 80.0 77.5 75.0 72.5 70.0 67.5 65.0 62.5 60.0 57.5 55.0 52.5 50.0 *Maximum Sense Current = 1.0 Amps for LM3814-1.0 ...
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