LM3812MX-7.0 National Semiconductor, LM3812MX-7.0 Datasheet
LM3812MX-7.0
Specifications of LM3812MX-7.0
Related parts for LM3812MX-7.0
LM3812MX-7.0 Summary of contents
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... LM3813-1.0) Connection Diagrams Top View LM3812 for High-Side Sensing © 2005 National Semiconductor Corporation n Low quiescent current in shutdown mode (typically 2.5 µ msec sampling interval Features n No external sense element required n PWM output indicates the current magnitude and ...
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... Ordering Information # Order No. Sense Range ± LM3812M-1.0 1A ± LM3812MX-1.0 1A ± LM3812M-7.0 7A ± LM3812MX-7.0 7A ± LM3813M-1.0 1A ± LM3813MX-1.0 1A ± LM3813M-7.0 7A ± LM3813MX-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 1 µF and filter capacitor is DD 0.1 µF. Symbol Parameter V Logic High Level for PWM OH V Logic Low ...
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Typical Performance Characteristics 0.1 µF. (Continued) PWM Frequency vs Supply Voltage Operating Current vs Supply Voltage Operating Current vs Temperature Supply bypass capacitor is 0.1 µF and filter capacitor is PWM Frequency vs Temperature 10012213 Shutdown Current vs Supply Voltage ...
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Typical Performance Characteristics 0.1 µF. (Continued) Current vs Duty Cycle Accuracy vs Temperature (LM3812-1.0 and LM3813-1.0) Error vs Current (LM3812-1.0 and LM3813-1.0) (Note 10) Note 10: These curves represent a statistical average such that the noise is insignificant. www.national.com Supply ...
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Typical Application Circuits In the application circuits, the 0.1 µF ceramic capacitor between pins 1 and 8 is used for bypassing, and the 0.1 µF ceramic capacitor between pins 3 and 4 is used for fil- tering. Shutdown (SD) is ...
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Typical Application Circuits is used for bypassing, and the 0.1 µF ceramic capacitor between pins 3 and 4 is used for filtering. Shutdown (SD) is tied to V through a 10 kΩ resistor. (Continued) DD FIGURE 3. Paralleling LM3812 for ...
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Typical Application Circuits is used for bypassing, and the 0.1 µF ceramic capacitor between pins 3 and 4 is used for filtering. Shutdown (SD) is tied to V through a 10 kΩ resistor. (Continued) DD FIGURE 4. High Voltage Operation ...
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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 1024 levels. Therefore, the duty cycle can change only in increments of 1/1024. 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 Sense Current (Amps)* 1.00 0.95 0.90 0.85 0.80 0.75 0.70 0.65 0.60 0.55 0.50 0.45 0.40 ...
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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 LM3812-1.0 ...
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