MCP121T-240E/LB Microchip Integrated Circuit (SOT23 (3-Pin)) In Stock
The MCP121T-240E/LB is a single-channel voltage supervisor and microprocessor reset IC from Microchip with a fixed 2.4 V threshold and open-drain active-low reset output in a compact 3-pin SC70 package. It monitors the supply rail and asserts reset to hold the processor in reset during power-up or brown-out events. Ideal for embedded systems requiring reliable power-on reset and undervoltage protection in space-constrained applications.
- Manufacturer
- Microchip
- Package
- SOT23 (3-Pin)
- Pin Count
- 3
- Lifecycle
- ACTIVE
- Datasheet
- MCP121T-240E/LB Datasheet PDF
- Category
- Integrated Circuit
- Price
- From $0.2450(MOQ 1)
- Temp Range
- -40.0°C to 125.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- Fixed 2.4 V undervoltage threshold for supply monitoring and reset generation
- Single-channel voltage supervisor with open-drain active-low reset output
- 3-pin SC70 package for ultra-compact footprints in portable designs
- RoHS-compliant and lead-free (Pbfree: Yes) construction
- No external components required — fixed threshold simplifies BOM
- 10-week factory lead time with long product lifecycle (YTEOL: 9)
Applications
The MCP121T-240E/LB is used in microcontroller and processor-based systems as a dedicated power-on reset supervisor, ensuring reliable initialization when the supply ramps up through 2.4 V. Its open-drain output allows easy connection to active-low reset pins on MCUs, FPGAs, and DSPs in IoT nodes, wearables, and battery-powered instruments. It is also applied in brown-out detection circuits for handheld medical devices and portable consumer electronics where uncontrolled restarts due to supply sag must be prevented.
Specifications
| Pbfree Code | Yes |
| Manufacturer Package Code | SC70-3 |
| Factory Lead Time | 10Weeks |
| YTEOL | 9 |
| Additional Feature | BAT BUP SW:N;MNL RST:N;OV DET:N;PW FL IP:N;PW FL IO:N;PW FL OP:N;PRG RST DLY:N;UV DET:N;WD:N;WWD:N |
| Adjustable Threshold | NO |
| Analog IC - Other Type | VOLTAGE SUPERVISOR/RESET IC |
| JESD-30 Code | R-PDSO-G3 |
| JESD-609 Code | e3 |
| Number of Channels | 1 |
| Number of Functions | 1 |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | TSSOP3/6,.08 |
| Package Shape | RECTANGULAR |
| Package Style | SMALL OUTLINE, THIN PROFILE, SHRINK PITCH |
| Peak Reflow Temperature (Cel) | 260 |
| Qualification Status | Not Qualified |
| Screening Level | TS 16949 |
| Supply Current-Max (Isup) | 0.02mA |
| Supply Voltage-Max (Vsup) | 5.5V |
| Supply Voltage-Min (Vsup) | 1V |
| Supply Voltage-Nom (Vsup) | 3V |
| Surface Mount | YES |
| Temperature Grade | AUTOMOTIVE |
| Terminal Finish | Matte Tin (Sn) |
| Terminal Form | GULL WING |
| Terminal Pitch | 0.65mm |
| Terminal Position | DUAL |
| Threshold Voltage-Nom | +2.32V |
| Time@Peak Reflow Temperature-Max (s) | 40 |
| Package | SOT23 (3-Pin) |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| Moisture Sensitivity Level | MSL 1 |
| ECCN | EAR99 |
| HTS Code | 8542.39.00.01 |
| Country of Origin | Thailand |
Alternate & Equivalent Parts
No known alternates. Submit an RFQ and our team can suggest alternatives.
Frequently Asked Questions
At what supply voltage does MCP121T-240E/LB assert its reset signal to halt the processor?
The MCP121T-240E/LB asserts its open-drain active-low reset output when the monitored supply falls below the fixed 2.4 V threshold, keeping the processor in reset until the supply recovers above that level plus any internal hysteresis, preventing erratic operation during power ramp or brown-out.
How does the open-drain output of MCP121T-240E/LB connect to an MCU reset pin?
The open-drain output of MCP121T-240E/LB requires an external pull-up resistor (typically 10 kΩ to 100 kΩ) connected to the MCU supply rail. This allows the RESET line to be wired-AND with other open-drain supervisors or manual reset buttons in a single 3-pin circuit without any logic-level conflict.
Why choose MCP121T-240E/LB over an adjustable-threshold supervisor for a fixed 2.4 V rail design?
For a fixed 2.4 V supply, MCP121T-240E/LB eliminates the 2-resistor voltage divider needed by adjustable-threshold supervisors, reducing BOM cost and PCB area. The 3-pin SC70 package combined with no external components gives the smallest possible reset supervisor solution at under 2 mm x 1.25 mm.
What is the procurement lead time and lifecycle outlook for MCP121T-240E/LB?
MCP121T-240E/LB has a factory lead time of 10 weeks and a YTEOL of 9, indicating it is expected to remain available for approximately 9 more years. Buyers can confidently design it into long-lifecycle industrial and medical equipment, though buffer stock is recommended given the 10-week replenishment window.
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| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 1+ | $0.5300 | $0.53 |
| 100+ | $0.4000 | $40.00 |
| 1000+ | $0.3300 | $330.00 |
| 1500+ | $0.3000 | $450.00 |
| 2250+ | $0.2800 | $630.00 |
| 3000+ | $0.2450 | $735.00 |
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