Electronic Components Datasheet Search |
|
LM5111-3MYX Datasheet(PDF) 10 Page - Texas Instruments |
|
LM5111-3MYX Datasheet(HTML) 10 Page - Texas Instruments |
10 / 19 page ISOURCE (MAX) := TJ(MAX) - TA TJA · VDIODE ISINK (MAX) := TJ(MAX) - TA TJA · RDS (ON) LM5111 SNVS300F – JULY 2004 – REVISED MAY 2011 www.ti.com Characterization of the LM5111 provides accurate estimates of the transient and quiescent power dissipation components. At 300 kHz switching frequency and 30 nC load used in the example, the transient power will be 8 mW. The 1 mA nominal quiescent current and 12V VGATE supply produce a 12 mW typical quiescent power. Therefore the total power dissipation PD = 0.216 + 0.008 + 0.012 = 0.236W. (3) We know that the junction temperature is given by TJ = PD x θJA + TA (4) Or the rise in temperature is given by TRISE = TJ − TA = PD x θJA (5) For SOIC package, θJA is estimated as 170°C/W for the conditions of natural convection. For VSSOP, θJA is typically 60°C/W. Therefore for SOIC TRISE is equal to TRISE = 0.236 x 170 = 40.1°C (6) CONTINUOUS CURRENT RATING OF LM5111 The LM5111 can deliver pulsed source/sink currents of 3A and 5A to capacitive loads. In applications requiring continuous load current (resistive or inductive loads), package power dissipation, limits the LM5111 current capability far below the 5A sink/3A source capability. Rated continuous current can be estimated both when sourcing current to or sinking current from the load. For example when sinking, the maximum sink current can be calculated as: where • RDS(on) is the on resistance of lower MOSFET in the output stage of LM5111 (7) Consider TJ(max) of 125°C and θJA of 170°C/W for an SO-8 package under the condition of natural convection and no air flow. If the ambient temperature (TA) is 60°C, and the RDS(on) of the LM5111 output at TJ(max) is 2.5 Ω, this equation yields ISINK(max) of 391mA which is much smaller than 5A peak pulsed currents. Similarly, the maximum continuous source current can be calculated as where • VDIODE is the voltage drop across hybrid output stage which varies over temperature and can be assumed to be about 1.1V at TJ(max) of 125°C (8) Assuming the same parameters as above, this equation yields ISOURCE(max) of 347mA. 10 Submit Documentation Feedback Copyright © 2004–2011, Texas Instruments Incorporated Product Folder Links: LM5111 |
Similar Part No. - LM5111-3MYX |
|
Similar Description - LM5111-3MYX |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |