LM22677TJE-5.0/NOPB National Semiconductor, LM22677TJE-5.0/NOPB Datasheet
LM22677TJE-5.0/NOPB
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LM22677TJE-5.0/NOPB Summary of contents
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... The LM22677 series also has built in thermal shut- down, current limiting and an enable control input that can power down the regulator to a low 25 µA quiescent current standby condition. Simplified Application Schematic © 2011 National Semiconductor Corporation LM22677/LM22677Q Features ■ Wide input voltage range: 4.5V to 42V ■ ...
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... Connection Diagram Ordering Information Output Order Number Voltage ADJ LM22677TJE-ADJ ADJ LM22677TJ-ADJ 5.0 LM22677TJE-5.0 5.0 LM22677TJ-5.0 ADJ LM22677QTJE-ADJ ADJ LM22677QTJ-ADJ 5.0 LM22677QTJE-5.0 5.0 LM22677QTJ-5.0 *Automotive Grade (Q) product incorporates enhanced manufacturing and support processes for the automotive market, including defect detection methodologies. ...
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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. VIN to GND EN Pin Voltage RT/SYNC Pin Voltage SW to GND (Note 2) BOOT Pin Voltage FB Pin Voltage Power Dissipation Electrical Characteristics junction temperature (T ) range of -40° ...
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Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur, including inoperability and degradation of device reliability and/or performance. Functional operation of the device and/or non-degradation at the Absolute Maximum Ratings or other conditions beyond ...
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Feedback Bias Current vs Temperature Standby Quiescent Current vs Input Voltage Normalized Feedback Voltage vs Input Voltage Normalized Enable Threshold Voltage vs Temperature 30074105 Normalized Feedback Voltage vs Temperature 30074106 Switching Frequency vs RT/SYNC Resistor 30074109 5 30074110 30074107 30074113 ...
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Typical Application Circuit and Block Diagram www.national.com FIGURE 1. 3. 600 kHz OUT 6 30074114 ...
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Detailed Operating Description The LM22677 switching regulator features all of the functions necessary to implement an efficient high voltage buck regu- lator using a minimum of external components. This easy to use regulator integrates a 42V N-Channel switch with an ...
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FIGURE 2. Output Current in Foldback vs. Nominal Duty Cycle The percentage of output current limit fold back is affected by duty cycle, inductance, and See Figure 2 for details. The current limit will only protect the inductor from a ...
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Self Synchronize It is also possible to self-synchronize multiple LM22677 reg- ulators to share the same switching frequency. This can be done by attaching the RT/SYNC pins together and putting a 1 kΩ resistor to ground. The diagram in Figure ...
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F is the switching frequency which is 500 kHz without an external frequency set resistor or external sync signal ap- plied to the RT/SYNC pin. If the switching frequency is set higher than 500kHz, the inductance value may not ...
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FIGURE 5. Resistive Feedback Divider A maximum value of 10 kΩ is recommended for the sum of R1 and R2 to keep high output voltage accuracy for the –ADJ option. A maximum of 2 kΩ is recommended for the ...
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Circuit Board Layout Board layout is critical for switching power supplies. First, the ground plane area must be sufficient for thermal dissipation purposes. Second, appropriate guidelines must be followed to reduce the effects of switching noise. Switch mode con- verters ...
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PCB Layout Example 13 30074125 www.national.com ...
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Schematic for Buck/Boost (Inverting) Application See AN-1888 for more information on the inverting (buck- boost) application generating a negative output voltage from a positive input voltage. www.national.com 30074126 14 ...
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Physical Dimensions inches (millimeters) unless otherwise noted 7-Lead Plastic TO-263 THIN Package NS Package Number TJ7A 15 www.national.com ...
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