SPX2945

400mA Low Dropout Voltage Regulator (LDOs)
Data Sheet

Description

The SPX2945 is a low power voltage regulator. This device is an excellent choice for use in battery powered applications such as cordless telephones, radio control systems and portable computers. The SPX2945 features very low quiescent current (100μA typical) and very low dropout voltage. This includes a tight initial tolerance of 1% max and very low output temperature coefficient, making the SPX2945 useful as a low power voltage reference.

The error flag output feature is used as power-on reset for warning of a low output voltage, due to a falling voltage input of batteries. Another feature is the logic-compatible shutdown input which enables the regulator to be switched on and off. The SPX2945 is offered in 3-pin TO-220 package, SO-8 (same pinout as SPX2951), SOT-223, surface mount 3-pin TO-252, 3-pin TO-263 packages and 5-pin TO-263.

The regulator output voltage (of the 8-pin SO-8) may be pin-strapped for a 3.3V and 5.0V or programmed from 1.24V to 20V with an external pair of resistors. Look for SPX2951 for 150mA and SPX2954 for 250mA applications.

Features

  • Output 3.3V, 5.0V at 400mA output
  • Very low quiescent current, 100µA
  • Low dropout voltage, 420mV at 400mA
  • Extremely tight load and line regulation
  • Very low temperature coefficient
  • Current and thermal limiting
  • Error flag warns of output dropout
  • Logic controlled electronic shutdown
  • Output programmable from 1.24V to 20V (for SO-8)

Application

Design Tools

Symbols & Footprints

Packaging

Pkg Code Details Quantities Dimensions PDF
NSOIC8
  • JEDEC Reference: MS-012
  • MSL Pb-Free: L1 @ 260ºC
  • MSL SnPb Eutectic: n/a
  • ThetaJA: 128.4ºC/W (std); 96.8ºC/W (fused)
  • Bulk Pack Style: Tube
  • Quantity per Bulk Pack: 98
  • Quantity per Reel: 2500
  • Quantity per Tube: 98
  • Quantity per Tray: n/a
  • Reel Size (Dia. x Width x Pitch): 330 x 12 x 8
  • Tape & Reel Unit Orientation: Quadrant 1
  • Dimensions: mm
  • Length: 4.90
  • Width: 3.90
  • Thickness: 1.75
  • Lead Pitch: 1.27
SOT-223-3
  • JEDEC Reference: TO-261
  • MSL Pb-Free: L1 @ 260ºC
  • MSL SnPb Eutectic: n/a
  • ThetaJA: 62.3ºC/W
  • Bulk Pack Style: Tube
  • Quantity per Bulk Pack: 78
  • Quantity per Reel: 2500
  • Quantity per Tube: 78
  • Quantity per Tray: n/a
  • Reel Size (Dia. x Width x Pitch): 330 x 12 x 8
  • Tape & Reel Unit Orientation: Heatsink by sprocket hole
  • Dimensions: mm
  • Length: 6.50
  • Width: 3.50
  • Thickness: 1.80
  • Lead Pitch: 2.30
TO-220-3
  • JEDEC Reference: TO-220
  • MSL Pb-Free: n/a
  • MSL SnPb Eutectic: n/a
  • ThetaJA: 29.4ºC/W
  • Bulk Pack Style: Tube
  • Quantity per Bulk Pack: n/a
  • Quantity per Reel: n/a
  • Quantity per Tube: 50
  • Quantity per Tray: n/a
  • Reel Size (Dia. x Width x Pitch): n/a
  • Tape & Reel Unit Orientation: n/a
  • Dimensions: inch
  • Length: 0.355 max
  • Width: 0.420 max
  • Thickness: 0.190 max
  • Lead Pitch: 0.10
TO-252-3
  • JEDEC Reference: TO-252
  • MSL Pb-Free: L2 @ 260ºC
  • MSL SnPb Eutectic: n/a
  • ThetaJA: 50ºC/W
  • Bulk Pack Style: Tube
  • Quantity per Bulk Pack: n/a
  • Quantity per Reel: 2000
  • Quantity per Tube: 80
  • Quantity per Tray: n/a
  • Reel Size (Dia. x Width x Pitch): 330 x 16 x 8
  • Tape & Reel Unit Orientation: Tab at sprocket hole.
  • Dimensions: inch
  • Length: 0.24
  • Width: 0.265 max
  • Thickness: 0.094 max
  • Lead Pitch: 0.09
TO-263-3
  • JEDEC Reference: TO-263
  • MSL Pb-Free: L3 @ 245ºC
  • MSL SnPb Eutectic: n/a
  • ThetaJA: 31.4ºC/W
  • Bulk Pack Style: Tube
  • Quantity per Bulk Pack: n/a
  • Quantity per Reel: 500
  • Quantity per Tube: 50
  • Quantity per Tray: n/a
  • Reel Size (Dia. x Width x Pitch): 330 x 24 x 16
  • Tape & Reel Unit Orientation: Tab away from sprocket hole.
  • Dimensions: inch
  • Length: 0.380 max
  • Width: 0.420 max
  • Thickness: 0.190
  • Lead Pitch: 0.10
TO-263-5
  • JEDEC Reference: TO-263
  • MSL Pb-Free: L3 @ 245ºC
  • MSL SnPb Eutectic: n/a
  • ThetaJA: 31.2ºC/W
  • Bulk Pack Style: Tube
  • Quantity per Bulk Pack: n/a
  • Quantity per Reel: 500
  • Quantity per Tube: 50
  • Quantity per Tray: n/a
  • Reel Size (Dia. x Width x Pitch): 330 x 24 x 16
  • Tape & Reel Unit Orientation: Tab away from sprocket hole.
  • Dimensions: inch
  • Length: 0.380 max
  • Width: 0.420 max
  • Thickness: 0.190
  • Lead Pitch: 0.067

Parts & Purchasing

Part Number Pkg Code RoHS Min Temp Max Temp Status Buy Now Order Samples
SPX2945M3-3-3 SOT-223-3 -40 125 OBS Suggested:
SPX2945M3-L-3-3
SPX2945M3-3-3/TR SOT-223-3 -40 125 OBS Suggested:
M3-L-3-3/TR
SPX2945M3-5-0 SOT-223-3 -40 125 OBS Suggested:
SPX2945M3-L-5-0
SPX2945M3-5-0/TR SOT-223-3 -40 125 OBS Suggested:
M3-L-5-0/TR
SPX2945M3-L-3-3 SOT-223-3 -40 125 OBS Suggested:
SPX2945M3-L-3-3/TR
SPX2945M3-L-3-3/TR SOT-223-3 -40 125 Active Order
SPX2945M3-L-5-0 SOT-223-3 -40 125 OBS Suggested:
SPX2945M3-L-5-0/TR
SPX2945M3-L-5-0/TR SOT-223-3 -40 125 OBS
SPX2945R-3-3 TO-252 OBS
SPX2945R-3-3/TR TO-252-3 -40 125 OBS
SPX2945R-5-0 TO-252-3 -40 125 OBS
SPX2945R-5-0/TR TO-252 OBS
SPX2945R-L-3-3 TO-252-3 -40 125 OBS
SPX2945R-L-3-3/TR TO-252 OBS
SPX2945R-L-5-0 TO-252-3 -40 125 OBS
SPX2945R-L-5-0/TR TO-252 OBS
SPX2945S-3-3 NSOIC8 -40 125 OBS
SPX2945S-3-3/TR NSOIC8 -40 125 OBS
SPX2945S-5-0 SOIC-8 OBS
SPX2945S-5-0/TR NSOIC8 OBS
SPX2945S-L-3-3 NSOIC8 OBS
SPX2945S-L-3-3/TR NSOIC8 -40 125 OBS
SPX2945S-L-5-0 NSOIC8 -40 125 OBS
SPX2945S-L-5-0/TR NSOIC8 OBS
SPX2945T-3-3 TO-263-3 -40 125 OBS
SPX2945T-3-3/TR TO-263-3 -40 125 OBS
SPX2945T-5-0 TO-263-3 -40 125 OBS
SPX2945T-5-0/TR TO-263-3 -40 125 OBS
SPX2945T5-3-3 TO-263-5 -40 125 OBS
SPX2945T5-3-3/TR TO-263-5 OBS
SPX2945T5-5-0 TO-263-5 OBS
SPX2945T5-5-0/TR TO-263-5 OBS
SPX2945T5-L-3-3 TO-263-5 OBS
SPX2945T5-L-3-3/TR TO-263-5 OBS
SPX2945T5-L-5-0 TO-263-5 -40 125 OBS
SPX2945T5-L-5-0/TR TO-263-5 OBS
SPX2945T-L-3-3 TO-263-3 -40 125 OBS
SPX2945T-L-3-3/TR TO-263-3 -40 125 OBS
SPX2945T-L-5-0 TO-263-3 -40 125 OBS
SPX2945T-L-5-0/TR TO-263-3 -40 125 OBS
SPX2945U-3-3 TO-220-3 -40 125 OBS
SPX2945U-5-0 TO-220-3 -40 125 OBS
SPX2945U-L-3-3 TO-220-3 -40 125 OBS
SPX2945U-L-5-0 TO-220-3 -40 125 OBS
Show obsolete parts
Part Status Legend
Active - the part is released for sale, standard product.
EOL (End of Life) - the part is no longer being manufactured, there may or may not be inventory still in stock.
CF (Contact Factory) - the part is still active but customers should check with the factory for availability. Longer lead-times may apply.
PRE (Pre-introduction) - the part has not been introduced or the part number is an early version available for sample only.
OBS (Obsolete) - the part is no longer being manufactured and may not be ordered.
NRND (Not Recommended for New Designs) - the part is not recommended for new designs.

Quality Documents

Part Number REACH
SPX2945M3-L-3-3 Download
SPX2945M3-L-3-3/TR Download
SPX2945M3-L-5-0/TR Download
Additional Quality Documentation may be available, please contact customersupport@maxlinear.com.
Distribution Date Description File
07/11/2017 Product Discontinuation Notification PDN_17-0623-01-1033.pdf
04/12/2017 Qualification of alternate assembly subcon, JCET. PCN 17-0207-01 JCET-1033.pdf
07/26/2016 Product discontinuation notification. Discontinued. PDN 16-0626-01-1033.pdf
09/09/2013 Addition of an alternate qualified SOT-223 assembly site, Carsem (Malaysia) using Hitachi CEL9240 molding compound, in addition to the current qualified assembly site, Unisem (Ipoh) using Sumitomo G600 molding compound. Material Change & Alternate Assembly Site. PCN_13-0623-02-1033.pdf
02/06/2012 Packing Change: The carrier tape size changed from 16x12 mm to 12x8 mm. Quantity per reel remains the same (2.5Ku per reel). Standardization and business consolidation. PCN_12-0106-1-1033.pdf
09/10/2008 Notice of Obsolescence –Selected Power Management Parts This is notification that the Power Management products listed on the attached page have been discontinued by Exar Corporation due to low market demand, effective immediately. PDN_080910-01-1033.pdf
02/28/2007 Product Obsolescence Letter and Discontinuation Notification. Discontinued. POL_022807-1033.pdf
02/02/2006 Announcing transfer of certain Power Management and Interface Products from Hillview fabrication and facility to wafer foundary Silan. See attached Product List Power Management and Interface products as listed are being transfer to external wafer foundry, due to cessation of operations of the sipex Hillview Fabrication manufacturing site PCN-06-0130-54-1033.pdf

Frequently Asked Questions

Yes. Try our Excel-based heat calculation spreadsheet ANP-03, Thermal Calculator
 
For further study, this spreadsheet is mentioned in the following helpful application note: ANP-02, Thermal Considerations for Linear Regulators 
  

The best way to determine this is to go to exar.com and type the part into the search function. At or near the top of the results you should see something that looks like
 
 

In this example, we looked for XRA1201. When you hover over it, it will turn grey and you can click anywhere in the grey box. This brings you to the product page. For example:

 
 

Click on Parts & Purchasing, highlighted in yellow above. The screen changes to:

 

Notice the status column and the “Show obsolete parts” link:

 

A legend tells you the definition of the different statuses. Click on the “Show obsolete parts” link to see EOL or OBS part numbers along with the Active part numbers:

 
 

Another method to find out if a part is OBS or EOL is to click on SUPPORT:

 

And then Product Change Notifications

 
 

Type the part into the search, and click on one of the part numbers from the drop down menu. Then you can look for the Product Discontinuation Notice, which generally is at the top of the list, for example:

 
 

If you see this, it tells you that this particular orderable part has been discontinued and when the last order date is, or was. If you click on the file, then you can view the notice we sent about this if you purchased the part in the recent past. It may also advise of a replacement part. When an orderable part first becomes discontinued, Product Discontinuation Notices are sent are sent to those who have purchased the parts in the recent past, if purchased directly, with a dated opportunity to place a last order.