Electronic Components Datasheet Search
  English  ▼

Delete All
ON OFF
ALLDATASHEET.COM

X  

Preview PDF Download HTML

LM2590HV Datasheet(PDF) 15 Page - National Semiconductor (TI)

[Old version datasheet] Texas Instruments acquired National semiconductor. Click here to check the latest version.
Part No. LM2590HV
Description  SIMPLE SWITCHER Power Converter 150 kHz 1A Step-Down Voltage Regulator, with Features
Download  20 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  NSC [National Semiconductor (TI)]
Direct Link  http://www.national.com
Logo NSC - National Semiconductor (TI)

LM2590HV Datasheet(HTML) 15 Page - National Semiconductor (TI)

Back Button LM2590HV Datasheet HTML 11Page - National Semiconductor (TI) LM2590HV Datasheet HTML 12Page - National Semiconductor (TI) LM2590HV Datasheet HTML 13Page - National Semiconductor (TI) LM2590HV Datasheet HTML 14Page - National Semiconductor (TI) LM2590HV Datasheet HTML 15Page - National Semiconductor (TI) LM2590HV Datasheet HTML 16Page - National Semiconductor (TI) LM2590HV Datasheet HTML 17Page - National Semiconductor (TI) LM2590HV Datasheet HTML 18Page - National Semiconductor (TI) LM2590HV Datasheet HTML 19Page - National Semiconductor (TI) Next Button
Zoom Inzoom in Zoom Outzoom out
 15 / 20 page
background image
Application Information (Continued)
Therefore, looking at
Figure 4 we quick-select a 100µH/1A
inductor (designed for 150 kHz operation) for this applica-
tion.
2. We should confirm that it is rated to handle 100 µJ (see
Figure 6) by the procedure shown in AN-1197 and that the
losses are acceptable. (If the DC Input voltage had been
greater than 40V we would need to consider e
CLIM as in
Example 2 above).
Note that we have taken V
SAT as 1.5V which includes an
estimated resistive drop across the inductor.
This completes the simplified inductor selection procedure.
For more general applications and better optimization, the
designer should refer to AN-1197.
Figure 8 provides helpful
contact information on suggested Inductor manufacturers
who may be able to recommend suitable parts, if the require-
ments are known.
FEEDFORWARD CAPACITOR
(Adjustable Output Voltage Version)
C
FF - A Feedforward Capacitor CFF, shown across R2 in
Figure 1 is used when the output voltage is greater than 10V
or when C
OUT has a very low ESR. This capacitor adds lead
compensation to the feedback loop and increases the phase
margin for better loop stability.
If the output voltage ripple is large (> 5% of the nominal
output voltage), this ripple can be coupled to the feedback
pin through the feedforward capacitor and cause the error
comparator to trigger the error flag. In this situation, adding a
resistor, R
FF, in series with the feedforward capacitor, ap-
proximately 3 times R1, will attenuate the ripple voltage at
the feedback pin.
INPUT CAPACITOR
C
IN — A low ESR aluminum or tantalum bypass capacitor is
needed between the input pin and ground pin. It must be
located near the regulator using short leads. This capacitor
prevents large voltage transients from appearing at the in-
put, and provides the instantaneous current needed each
time the switch turns on.
The important parameters for the Input capacitor are the
voltage rating and the RMS current rating. Because of the
relatively high RMS currents flowing in a buck regulator’s
input capacitor, this capacitor should be chosen for its RMS
current rating rather than its capacitance or voltage ratings,
although the capacitance value and voltage rating are di-
rectly related to the RMS current rating. The voltage rating of
the capacitor and its RMS ripple current capability must
never be exceeded.
OUTPUT CAPACITOR
C
OUT — An output capacitor is required to filter the output
and provide regulator loop stability. Low impedance or low
ESR Electrolytic or solid tantalum capacitors designed for
switching regulator applications must be used. When select-
ing an output capacitor, the important capacitor parameters
are; the 100 kHz Equivalent Series Resistance (ESR), the
RMS ripple current rating, voltage rating, and capacitance
value. For the output capacitor, the ESR value is the most
important parameter. The ESR should generally not be less
than 100 m
Ω or there will be loop instability. If the ESR is too
large, efficiency and output voltage ripple are effected. So
ESR must be chosen carefully.
CATCH DIODE
Buck regulators require a diode to provide a return path for
the inductor current when the switch turns off. This must be
a fast diode and must be located close to the LM2590HV
using short leads and short printed circuit traces.
Because of their very fast switching speed and low forward
voltage drop, Schottky diodes provide the best performance,
especially in low output voltage applications (5V and lower).
Ultra-fast recovery, or High-Efficiency rectifiers are also a
good choice, but some types with an abrupt turnoff charac-
teristic may cause instability or EMI problems. Ultra-fast
recovery diodes typically have reverse recovery times of 50
ns or less. The diode must be chosen for its average/RMS
current rating and maximum voltage rating. The voltage
rating of the diode must be greater than the DC input voltage
(not the output voltage).
SHUTDOWN /SOFT-START
This reduction in start up current is useful in situations where
the input power source is limited in the amount of current it
can deliver. In some applications Soft-start can be used to
replace undervoltage lockout or delayed startup functions.
If a very slow output voltage ramp is desired, the Soft-start
capacitor can be made much larger. Many seconds or even
minutes are possible.
If only the shutdown feature is needed, the Soft-start capaci-
tor can be eliminated.
www.national.com
15


Similar Part No. - LM2590HV

ManufacturerPart No.DatasheetDescription
Texas Instruments
Texas Instruments
LM2590HV TI-LM2590HV Datasheet
727Kb / 22P
[Old version datasheet]   LM2590HV SIMPLE SWITCHERPower Converter 150 kHz 1A Step-Down Voltage
LM2590HV TI1-LM2590HV Datasheet
1Mb / 35P
[Old version datasheet]   SIMPLE SWITCHER Power Converter
National Semiconductor (TI)
National Semiconductor ...
LM2590HV-AQ NSC-LM2590HV-AQ Datasheet
885Kb / 22P
   SIMPLE SWITCHER짰Power Converter 150 kHz 1A Step-Down Voltage Regulator, with Features
Texas Instruments
Texas Instruments
LM2590HV-AQ-Q1 TI1-LM2590HV-AQ-Q1 Datasheet
3Mb / 30P
[Old version datasheet]   SIMPLE SWITCHER Power Converter Step-Down Voltage Regulator
LM2590HVS-3.3/NOPB TI1-LM2590HVS-3.3/NOPB Datasheet
1Mb / 35P
[Old version datasheet]   SIMPLE SWITCHER Power Converter
More results

Similar Description - LM2590HV

ManufacturerPart No.DatasheetDescription
National Semiconductor (TI)
National Semiconductor ...
LM2598 NSC-LM2598 Datasheet
847Kb / 33P
   SIMPLE SWITCHER Power Converter 150 kHz 1A Step-Down Voltage Regulator, with Features
LM2590HV-AQ NSC-LM2590HV-AQ Datasheet
885Kb / 22P
   SIMPLE SWITCHER짰Power Converter 150 kHz 1A Step-Down Voltage Regulator, with Features
Texas Instruments
Texas Instruments
LM2598 TI1-LM2598_13 Datasheet
2Mb / 45P
[Old version datasheet]   SIMPLE SWITCHER짰 Power Converter 150 kHz 1A Step-Down Voltage Regulator with Features
National Semiconductor (TI)
National Semiconductor ...
LM2591HV NSC-LM2591HV Datasheet
730Kb / 20P
   SIMPLE SWITCHER Power Converter 150 kHz 1A Step-Down Voltage Regulator
LM2595 NSC-LM2595 Datasheet
935Kb / 29P
   SIMPLE SWITCHER Power Converter 150 kHz 1A Step-Down Voltage Regulator
LM2597 NSC-LM2597 Datasheet
900Kb / 34P
   SIMPLE SWITCHER Power Converter 150 kHz 0.5A Step-Down Voltage Regulator, with Features
LM2593HV NSC-LM2593HV Datasheet
753Kb / 21P
   SIMPLE SWITCHER Power Converter 150 kHz 2A Step-Down Voltage Regulator, with Features
LM2599 NSC-LM2599 Datasheet
812Kb / 31P
   SIMPLE SWITCHER Power Converter 150 kHz 3A Step-Down Voltage Regulator, with Features
Texas Instruments
Texas Instruments
LM2595 TI1-LM2595_13 Datasheet
3Mb / 41P
[Old version datasheet]   SIMPLE SWITCHER짰 Power Converter 150 kHz 1A Step-Down Voltage Regulator
National Semiconductor (TI)
National Semiconductor ...
LM2599 NSC-LM2599_00 Datasheet
817Kb / 32P
   SIMPLE SWITCHER짰 Power Converter 150 kHz 3A Step-Down Voltage Regulator, with Features
More results


Html Pages

1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19  20 


Datasheet Download

Go To PDF Page


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


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
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