LM/-Q1 does not rely on output capacitor ESR An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in. LM Synchronous 1MHz A Step-Down Voltage Regulator from the PowerWise® Family The LM Synchronously Rectified Buck Converter features all. The LM Synchronously Rectified Buck Converter Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
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Vias should be added to connect the ground of the input capacitors to a ground plane, located as close to the capacitor as possible. Except where mandated by applicable law, testing of all parameters of each component is not necessarily performed. A nF capacitor is used in this demonstration board. Determine the inductance The main parameter affected by the inductor is the amplitude dtaasheet the inductor current ripple ILR. Headline Bold Ipsum lorem Headline Light. Nonetheless, such components are subject to these dayasheet.
The inductor L1 should be connected close to the SW pin with as short a trace as possible to reduce the potential for EMI electromagnetic interference generation.
AN-1646 LM3102 Demonstration Board
Resale of TI components or services with statements different from or beyond the parameters stated by TI for that component or service voids all express and any implied warranties for the associated TI component or service and is an unfair and deceptive business practice. Once ILR is selected, L can be determined by: It must be as neat and compact as possible, and all external components must be as close to their associated pins of the LM as possible.
The bootstrap capacitor C4 should be connected as close to the SW and BST pins as possible, and the connecting traces should be thick. Calculate the feedback resistors The ratio of the feedback resistors can be calculated from the following equation: The capacitor at the SS pin determines the soft-start time, that is, the time for the reference voltage at the regulation comparator and the output voltage to reach their final value.
The average current during the on-time is the load current.
Buyer will fully indemnify TI and its representatives against any damages arising out of the use of any TI components in safety-critical applications. Additionally the use of thick traces, where possible, can help conduct heat away from the LM TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or other intellectual property right relating to any combination, machine, or process in which TI components or services are used.
Datasyeet ensure that the on-time is larger than the minimum limit, which is ns, the value of R1 must satisfy the following equation: A load which creates significant transients requires a larger output capacitor than a fixed load. Using numerous vias to connect the die attached pad to the ground plane is a good practice.
LM Datasheet(PDF) – National Semiconductor (TI)
The time is determined from the following equation: The Constant On-Time COT regulation scheme requires no loop compensation, results in a fast load transient response and simple circuit implementation that allows datashedt low component count, and consequently very small overall board space is required for a typical application.
The design of the demonstration board is detailed below. Determine the value of other components C1 and C2: Calculate the on-time setting resistor The switching frequency fSW of the demonstration board is affected dtasheet the on-time ton of the LM, which is determined by R1.
If the output voltage is higher than 1. The output capacitor C10, C11 should be connected close to the load and tied directly to the ground plane. The function of the input capacitor is to supply most of the main MOSFET current during the on-time, and limit the l3102 ripple at the VIN pin, assuming that the voltage source feeding to the VIN pin has finite output impedance. Buyer acknowledges and agrees that datahseet military or aerospace use of TI components which have not been so designated is solely at the Buyer’s risk, datwsheet that Buyer is solely responsible for compliance with all legal and regulatory daatsheet in connection with such use.
It then drops to zero at turn-off. For a worst case calculation, the input capacitor must be capable of supplying this average load current dxtasheet the maximum on-time. Typical performance and operating waveforms are also provided for reference. The input capacitor is calculated from: Products Applications Audio www. I wish to measure a very low resistance of the order of an ohm. Buyers are responsible for their datasneet and applications using TI components.
The operating frequency remains constant with line variations due to the inverse relationship between the input voltage and the on-time. Information published by TI regarding third-party products or services does not constitute a license to use such products or services or a warranty or endorsement thereof. In some cases, TI components may be promoted specifically to facilitate safety-related applications.
No TI components are authorized for use in FDA Class III or similar life-critical medical equipment unless authorized officers of the parties have executed a special agreement specifically governing such use. Lab 6 in this note.
Experimentation is usually necessary to determine the minimum value for the output capacitor, as the nature of the load may require a larger fatasheet. Judicious positioning of the PC board within the end product, along with the use of any available air flow forced or natural convection can datashee reduce the junction temperature.
C8 should be no smaller than nF for stability, and should be a good quality, low ESR, ceramic capacitor. Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which anticipate dangerous consequences of vatasheet, monitor failures and their consequences, lessen the likelihood of failures that might cause harm and take appropriate remedial actions. Testing and other quality control techniques are used to the extent TI lm31002 necessary to support this warranty.
Low ESR also helps ensure a complete recharge during each off-time. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and complete.
Buyer acknowledges and agrees that it is solely responsible for compliance with all legal, regulatory and safety-related requirements concerning its products, and any use of TI components in its applications, notwithstanding any applications-related information or support that may be provided by TI.
Synchronous 1MHz 2.5A Step-Down Voltage Regulator
Use of such information may require a license from a third party under the patents or other intellectual property of the third party, or a license from TI under the patents or other intellectual property of TI. In this demonstration board, a 10 nF capacitor is used. The connection from the PGND pin to the input capacitors should be as short and direct as possible. A low ESR 0.