Overview
| Information | 300mA Low Dropout Voltage Regulator (LDOs) |
|---|---|
| Output Option | Fixed |
| VOUT (V) | 3.3, 5.0 |
| VOUT Adj MIN (V) | - |
| VOUT Adj MAX (V) | - |
| IOUT (mA) | 300 |
| VIN MIN (V) | 4.1 |
| VIN MAX (V) | 20 |
| IQ (µA) | 150 |
| Accuracy (%) | 1% |
| Vdrop (mV) | 300 |
| Output Noise (µVRMS) | - |
| PSRR (dB) | 50 |
| Junction Temp Range (°C) | -40 to 125 |
| Package | SOT223-3 |
| Features | Reverse battery protection, Current limit and thermal protection |
The SPX 1521 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 SPX1521 features very low quiescent current and very low dropout voltage. This includes a tight initial tolerance of ±1% max and very low output temperature coefficient, making the SPX1521 useful as a low power voltage reference.
The SPX1521 is offered in 3 pin TO-252, SOT-223, TO-220 and TO-263 packages.
- 1% output accuracy 3.3V, 5V, at 300mA output
- Very low quiescent current
- 0.3V (typical) dropout voltage at 300mA
- Extremely tight load and line regulation
- Current and thermal limiting
- Reverse battery protection
- Equivalent replacement for LT1521
Documentation & Design Tools
| Type | Title | Version | Date | File Size |
|---|---|---|---|---|
| Data Sheets | SPX1521 300mA Low Dropout Voltage Regulator (LDOs) | 1.0.0 | May 2007 | 595.3 KB |
| Product Brochures | Power Management Brochure | R03 | April 2025 | 6.2 MB |
Parts & Purchasing
| Part Number | Pkg Code | Min Temp | Max Temp | Status | Suggested Replacement | PDN |
|---|---|---|---|---|---|---|
| SPX1521M3-3-3 | SOT-223-3 | -40 | 125 | OBS | ||
| SPX1521M3-3-3/TR | SOT-223-3 | -40 | 125 | OBS | ||
| SPX1521M3-5-0 | SOT-223-3 | -40 | 125 | OBS | ||
| SPX1521M3-5-0/TR | SOT-223-3 | -40 | 125 | OBS | ||
| SPX1521M3-L-3-3 | SOT-223-3 | -40 | 125 | OBS | ||
| SPX1521M3-L-3-3/TR | SOT-223-3 | -40 | 125 | OBS | ||
| SPX1521M3-L-5-0 | SOT-223-3 | -40 | 125 | OBS | ||
| SPX1521M3-L-5-0/TR | SOT-223-3 | -40 | 125 | OBS | SPX3940M3-L-5-0/TR | |
| SPX1521R-3-3 | TO-252-3 | OBS | ||||
| SPX1521R-3-3/TR | TO-252-3 | OBS | ||||
| SPX1521R-5-0 | TO-252-3 | OBS | ||||
| SPX1521R-5-0/TR | TO-252-3 | OBS | ||||
| SPX1521R-L-3-3 | TO-252-3 | OBS | ||||
| SPX1521R-L-3-3/TR | TO-252-3 | OBS | ||||
| SPX1521R-L-5-0 | TO-252-3 | OBS | ||||
| SPX1521R-L-5-0/TR | TO-252-3 | OBS | ||||
| SPX1521T-3-3 | TO-263-3 | OBS | ||||
| SPX1521T-3-3/TR | TO-263-3 | OBS | ||||
| SPX1521T-5-0 | TO-263-3 | OBS | ||||
| SPX1521T-5-0/TR | TO-263-3 | OBS | ||||
| SPX1521T-L-3-3 | TO-263-3 | OBS | ||||
| SPX1521T-L-3-3/TR | TO-263-3 | OBS | ||||
| SPX1521T-L-5-0 | TO-263-3 | -40 | 125 | OBS | ||
| SPX1521T-L-5-0/TR | TO-263-3 | OBS | ||||
| SPX1521U-3-3 | TO-220-3 | OBS | ||||
| SPX1521U-5-0 | TO-220-3 | OBS | ||||
| SPX1521U-L-3-3 | TO-220-3 | OBS | ||||
| SPX1521U-L-5-0 | TO-220-3 | OBS |
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.
Packaging
| Pkg Code | Details | Quantities | Dimensions |
|---|---|---|---|
| SOT-223-3 |
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| TO-220-3 |
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| TO-252-3 |
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| TO-263-3 |
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Notifications
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