LM2717-ADJ_08 NSC [National Semiconductor], LM2717-ADJ_08 Datasheet
LM2717-ADJ_08
Related parts for LM2717-ADJ_08
LM2717-ADJ_08 Summary of contents
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... External soft-start pins for each converter enables the user to tailor the soft-start times to a specific ap- plication. Each converter may also be shut down indepen- dently with its own shutdown pin. The LM2717-ADJ is available in a low profile 24-lead TSSOP package ensuring a low profile overall solution. ...
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... Connection Diagram Ordering Information Order Number Spec LM2717MT-ADJ LM2717MTX-ADJ LM2717MT-ADJ NOPB LM2717MTX-ADJ NOPB www.national.com Top View 20167904 24-Lead TSSOP Package Type NSC Package Drawing TSSOP-24 MTC24 TSSOP-24 MTC24 TSSOP-24 MTC24 TSSOP-24 MTC24 2 Supplied As 61 Units, Rail 2500 Units, Tape and Reel ...
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Pin Descriptions Pin Name 1 PGND Power ground. PGND and AGND pins must be connected together directly at the part. 2 PGND Power ground. PGND and AGND pins must be connected together directly at the part. 3 AGND Analog ground. ...
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Block Diagram www.national.com 4 20167903 ...
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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 SW1 Voltage SW2 Voltage FB1, FB2 Voltages CB1, CB2 Voltages V Voltage C1 V Voltage 0.965V C2 ...
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Symbol Parameter I Buck 1 Shutdown Pin Current 0V < V SHDN1 I Buck 2 Shutdown Pin Current 0V < V SHDN2 I Buck 1 Switch Leakage L1 Current I Buck 2 Switch Leakage L2 Current R Buck 1 Switch ...
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Typical Performance Characteristics Shutdown I vs. Input Voltage Q Switching Frequency vs. Input Voltage (F = 300kHz) SW Buck 2 R vs. Input Voltage DS(ON) Switching I 20167960 Buck 1 R 20167962 Buck 1 Efficiency vs. Load Current 20167964 7 ...
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Buck 2 Efficiency vs. Load Current (V = 15V) OUT Buck 1 Switch Current Limit vs. Input Voltage Buck 1 Switch Current Limit vs. Temperature (V = 12V) IN www.national.com Buck 2 Efficiency vs. Load Current 20167966 Buck 2 Switch ...
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... The output voltage is defined approximately as: where D is the duty cycle of the switch, D and D quired for design calculations. The LM2717-ADJ has a minimum switch ON time which cor- responds to a minimum duty cycle of approximately 10% at 600kHz operation and approximately 5% at 300kHz opera- tion. In the case of some high voltage differential applications ...
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... R SOFT-START CAPACITOR (BOTH REGULATORS) The LM2717-ADJ contains circuitry that can be used to limit the inrush current on start-up of the DC/DC switching regula- tors. This inrush current limiting circuitry serves as a soft-start. ...
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... Loop gain is equal to the product of control-output transfer function and the output-control transfer function (the compensation network transfer func- tion). The DC loop gain of the LM2717 is usually around 55dB to 60dB when loaded. Generally speaking good idea to have a loop gain slope that is -20dB /decade from a very low frequency to well beyond the crossover frequency ...
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... LAYOUT CONSIDERATIONS The LM2717-ADJ uses two separate ground connections, PGND for the drivers and boost NMOS power device and AGND for the sensitive analog control circuitry. The AGND and PGND pins should be tied directly together at the pack- age ...
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Application Information Some Recommended Inductors (Others May Be Used) Manufacturer Coilcraft TDK Pulse Sumida Some Recommended Input And Output Capacitors (Others May Be Used) Manufacturer Vishay Sprague Taiyo Yuden Cornell Dubilier MuRata Inductor DO3316 and DT3316 series SLF10145 series P0751 ...
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FIGURE 5. 5V, 3.3V Output Application FIGURE 6. 3.3V, 1.8V Output Application 14 20167959 20167915 ...
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Physical Dimensions inches (millimeters) unless otherwise noted For Ordering, Refer to Ordering Information Table TSSOP-24 Pin Package (MTC) NS Package Number MTC24 15 www.national.com ...
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