| PartNumber | SI9121DY-3-E3 | SI9121DY-3-T1-E3 | SI9121DY-5-E3 |
| Description | Switching Voltage Regulators Hi-V Buck/Boost 3V Converter | Switching Voltage Regulators Hi-V Buck/Boost 3V Converter | Switching Voltage Regulators Hi-V Buck/Boost 5V Converter |
| Manufacturer | Vishay | Vishay | Vishay |
| Product Category | Switching Voltage Regulators | Switching Voltage Regulators | Switching Voltage Regulators |
| RoHS | Y | Y | Y |
| Mounting Style | SMD/SMT | SMD/SMT | SMD/SMT |
| Package / Case | SOIC-Narrow-8 | SOIC-Narrow-8 | SOIC-Narrow-8 |
| Output Voltage | 3.3 V | 3.3 V | 5 V |
| Output Current | 10 mA to 250 mA | 10 mA to 250 mA | 10 mA to 250 mA |
| Number of Outputs | 1 Output | 1 Output | 1 Output |
| Topology | Boost, Buck | Boost, Buck | Boost, Buck |
| Switching Frequency | 95 kHz | 95 kHz | 95 kHz |
| Packaging | Tube | Reel | Tube |
| Product | Voltage Regulators | Voltage Regulators | Voltage Regulators |
| Type | Step-Down Regulator | Synchronous Step-Down DC/DC Converter | Step-Down Regulator |
| Brand | Vishay / Siliconix | Vishay / Siliconix | Vishay / Siliconix |
| Product Type | Switching Voltage Regulators | Switching Voltage Regulators | Switching Voltage Regulators |
| Factory Pack Quantity | 500 | 2500 | 500 |
| Subcategory | PMIC - Power Management ICs | PMIC - Power Management ICs | PMIC - Power Management ICs |
| Unit Weight | 0.006596 oz | 0.006596 oz | 0.006596 oz |
| Part # Aliases | - | SI9121DY-3-E3 | - |