LM3822MM-1.0/NOPB National Semiconductor, LM3822MM-1.0/NOPB Datasheet
LM3822MM-1.0/NOPB
Specifications of LM3822MM-1.0/NOPB
LM3822MM-1.0TR
Related parts for LM3822MM-1.0/NOPB
LM3822MM-1.0/NOPB Summary of contents
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... Connection Diagram © 2004 National Semiconductor Corporation n Low quiescent current in shutdown mode (typically 1.8 µ msec sampling interval n In MSOP-8 Package Features n No external sense element required ...
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... LM3822MM-1.0 1.0A ± LM3822MMX-1.0 1.0A ± LM3822MM-2.0 2.0A ± LM3822MMX-2.0 2.0A * Current is sampled over a fixed interval. The average current during this interval is indicated by the duty cycle of the PWM output during next interval. Pin Description (High-Side, LM3822) Pin Name 1 SENSE GND ...
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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 Specifications in standard type face are for T ranges. (Continued) Common Device Parameters Unless otherwise specified 3.6V for the following specifications. Supply bypass capacitor is 1 µF and filter capacitor is DD 0.1 µF. Symbol Parameter ...
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Typical Performance Characteristics 0.1 µF. Measured Current vs Actual Current (LM3822-1.0) PWM Frequency vs Supply Voltage Operating Current vs Supply Voltage Supply bypass capacitor is 0.1 µF and filter capacitor is Measured Current vs Actual Current 10124924 PWM Frequency vs ...
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Typical Performance Characteristics 0.1 µF. (Continued) Operating Current vs Temperature Current vs PWM Duty Cycle Accuracy vs Temperature (LM3822-1.0) Note 10: These curves represent a statistical average such that the noise is insignificant. www.national.com Supply bypass capacitor is 0.1 µF ...
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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. DD FIGURE 2. Paralleling LM3822 for Higher ...
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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. High Voltage Operation ...
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Product Operation The current is sampled by the delta-sigma modulator, as illustrated in Figure 4. 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 TABLE 1. Current to Duty Cycle Conversion Table Sense Current (Imax = 1.0A) 1 0.95 0.90 ...
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Timing Diagram Duty cycle of the PWM waveform during any sampling interval indicates the current magnitude (average) and direction during the previous sampling interval. FIGURE 6. Typical Timing Diagram for Mostly Positive Current www.national.com 12 10124911 ...
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