MCP809T-300I/TT Microchip Integrated Circuit (SOT23 (3-Pin)) In Stock
MCP809T-300I/TT is a single-channel microprocessor supervisor and reset IC from Microchip with a fixed 2.925 V threshold voltage. It asserts an active-low reset output whenever the monitored supply falls below 2.925 V, ensuring controlled startup and brownout protection. Supplied in a tiny 3-pin SOT-23 package for space-critical embedded and IoT applications.
- Manufacturer
- Microchip
- Package
- SOT23 (3-Pin)
- Pin Count
- 3
- Lifecycle
- ACTIVE
- Datasheet
- MCP809T-300I/TT Datasheet PDF
- Category
- Integrated Circuit
- Price
- From $0.2622(MOQ 1)
- Temp Range
- -40.0°C to 85.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
What are the key features of MCP809T-300I/TT?
- Fixed 2.925 V threshold with tight accuracy monitors 3.3 V rails and asserts active-low reset during undervoltage or brownout without any external components
- Single-channel supervisor in a 3-pin SOT-23 package occupies minimal PCB footprint for integration on densely populated microcontroller boards
- Internal power-on reset delay ensures the supply is stable before releasing the RESET pin, preventing spurious microcontroller startup faults
What is MCP809T-300I/TT used for?
The MCP809T-300I/TT is designed to supervise 3.3 V power rails in microcontroller-based systems, ensuring that the processor is held in reset during power-up, brownout, and supply-glitch conditions. It is commonly used in industrial controllers, smart meters, and IoT gateway boards where uncontrolled resets from supply noise can corrupt non-volatile memory or interrupt critical processes. The tiny 3-pin SOT-23 footprint allows it to be placed close to the microcontroller's reset pin with negligible additional board area.
What are the specifications of MCP809T-300I/TT?
| Pbfree Code | Yes |
| Manufacturer Package Code | SOT-23-3 |
| Factory Lead Time | 8Weeks |
| YTEOL | 8 |
| 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 | TO-236 |
| Package Shape | RECTANGULAR |
| Package Style | SMALL OUTLINE, THIN PROFILE |
| Peak Reflow Temperature (Cel) | 260 |
| Qualification Status | Not Qualified |
| Supply Current-Max (Isup) | 0.06mA |
| Supply Voltage-Max (Vsup) | 5.5V |
| Supply Voltage-Min (Vsup) | 1V |
| Supply Voltage-Nom (Vsup) | 2.85V |
| Surface Mount | YES |
| Temperature Grade | INDUSTRIAL |
| Terminal Finish | Matte Tin (Sn) |
| Terminal Form | GULL WING |
| Terminal Pitch | 0.96mm |
| Terminal Position | DUAL |
| Threshold Voltage-Nom | +2.925V |
| 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 |
Where can I find the MCP809T-300I/TT datasheet?
MCP809T-300I/TT Datasheet DownloadOfficial datasheet from Microchip
What are equivalent replacements for MCP809T-300I/TT?
No known alternates. Submit an RFQ and our team can suggest alternatives.
Frequently Asked Questions
At what supply voltage does the MCP809T-300I/TT assert its reset output?
The MCP809T-300I/TT asserts the active-low RESET output whenever the monitored supply falls below the fixed threshold of 2.925 V. This threshold is factory-trimmed, so no external resistor divider is needed. The reset output releases after a built-in delay once the supply recovers above 2.925 V, protecting the microcontroller from operating in an undefined undervoltage state.
Why use a dedicated supervisor IC like the MCP809T-300I/TT instead of relying on a microcontroller's internal brown-out detection?
An on-chip brown-out detector is powered from the same rail it monitors, so it may not function correctly or assert reset fast enough as the supply collapses. The MCP809T-300I/TT monitors the rail externally and draws only microamp-level supply current, ensuring reset is asserted well before the microcontroller enters an undefined state, preventing data corruption in flash or EEPROM at voltages below 2.925 V.
Is the MCP809T-300I/TT suitable for monitoring 3.3 V rails in battery-powered IoT devices?
Yes. The 2.925 V threshold corresponds to the typical low-voltage warning point of a regulated 3.3 V rail, and the device's ultra-low quiescent current makes it compatible with battery-powered nodes that must minimize standby drain. The 3-pin SOT-23 package also contributes negligible weight and board space to compact IoT sensor modules.
How does the built-in reset delay of the MCP809T-300I/TT help at power-on?
After the supply rises above 2.925 V, the MCP809T-300I/TT holds RESET asserted for a fixed timeout period (typically 140 ms at 3.3 V). This delay allows the power supply's output capacitors to charge fully and the oscillator to stabilize before the processor begins executing code, preventing erratic startup behavior caused by marginal or slowly rising supply rails.
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More from Microchip
| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 1+ | $0.2990 | $0.30 |
| 6+ | $0.2641 | $1.58 |
| 48000+ | $0.2622 | $12585.60 |
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