MCP121-450E/TO Microchip Integrated Circuit (Other) In Stock

Name: MCP121-450E/TO
Brand: Microchip
SKU: MCP121-450E/TO
Availability: InStock

The MCP121-450E/TO is a single-channel voltage supervisor and reset IC with a fixed 4.50 V trip threshold, asserting a reset output when supply voltage drops below the threshold. It is housed in a 3-pin TO-92 package for reliable MCU and processor power monitoring.

ACTIVEIntegrated CircuitVerified Jun 2026

Package / Visual Reference

MCP121-450E/TOOther

Quick Facts

Manufacturer: Microchip
Package: Other
Pin Count: 3
Lifecycle: ACTIVE
Datasheet: MCP121-450E/TO Datasheet PDF
Category: Integrated Circuit
Price: From $0.2350(MOQ 1)
Temp Range: -40.0°C to 125.0°C
RoHS: Compliant
Lead Time: 3–7 business days
Shipping: DHL Express · Worldwide

What are the key features of MCP121-450E/TO?

Fixed 4.50 V reset threshold voltage for precise supply undervoltage detection
Single-channel voltage supervisor with active-low reset output
3-pin TO-92 through-hole package for easy board integration
Manual reset input not included, keeping design minimal and cost-effective
No adjustable threshold — fixed trip point reduces BOM and simplifies design
7-week factory lead time with industrial-grade operating temperature range

What is MCP121-450E/TO used for?

The MCP121-450E/TO is used to monitor the power supply rail of 5 V microcontrollers, embedded processors, and digital logic systems, asserting a reset signal whenever the supply drops below 4.50 V to prevent corrupted program execution. It is a standard choice for industrial control panels, motor drive boards, and power-cycle-sensitive data logging equipment where reliable startup and brownout protection are required.

What are the specifications of MCP121-450E/TO?

Pbfree Code	Yes
Manufacturer Package Code	TO-92-3
Factory Lead Time	7Weeks
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	O-PBCY-T3
JESD-609 Code	e3
Number of Channels	1
Number of Functions	1
Package Body Material	PLASTIC/EPOXY
Package Equivalence Code	SIP3,.1,50
Package Shape	ROUND
Package Style	CYLINDRICAL
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	NO
Temperature Grade	AUTOMOTIVE
Terminal Finish	Matte Tin (Sn)
Terminal Form	THROUGH-HOLE
Terminal Position	BOTTOM
Threshold Voltage-Nom	+4.38V
Package	Other

Compliance & Regulatory

RoHS Status	Compliant
Lead-Free	Yes (Pb-Free)
ECCN	EAR99
HTS Code	8542.39.00.60
Country of Origin	Philippines, Taiwan

Where can I find the MCP121-450E/TO datasheet?

MCP121-450E/TO Datasheet Download

Official datasheet from Microchip

What are equivalent replacements for MCP121-450E/TO?

No known alternates. Submit an RFQ and our team can suggest alternatives.

Frequently Asked Questions

At what supply voltage does MCP121-450E/TO assert its reset output to protect a 5 V microcontroller?

The MCP121-450E/TO asserts the active-low reset output whenever the monitored supply voltage drops below the fixed 4.50 V threshold, holding the MCU in reset until the supply recovers above that level.

Why would a designer choose a fixed-threshold reset IC like MCP121-450E/TO over an adjustable supervisor?

A fixed 4.50 V threshold eliminates the external resistor divider required for adjustable parts, reducing component count by 2 resistors, cutting BOM cost, and removing a possible failure point in space-constrained designs.

How does the TO-92 package of MCP121-450E/TO compare to SOT-23 reset ICs in a production assembly context?

The TO-92 through-hole package is easier to hand-solder during prototyping and field repair, while SOT-23 saves more board area in SMT designs. Both provide equivalent voltage supervision functionality at the 4.50 V trip level.

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AvailabilityIn Stock

Reference Price (USD)

From $0.2350

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Qty.	Unit Price	Ext. Price
1+	$0.5300	$0.53
10+	$0.4860	$4.86
25+	$0.4540	$11.35
100+	$0.4000	$40.00
1000+	$0.2400	$240.00
2000+	$0.2350	$470.00

pcs

Unit price: $0.5300 · Total: $0.53

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Lead Time3-7 business days

MOQFrom 1 piece

ShippingDHL / FedEx / UPS

OriginChina (Authorized)

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MCP121-450E/TO Microchip Integrated Circuit (Other) In Stock

What are the key features of MCP121-450E/TO?

What is MCP121-450E/TO used for?

What are the specifications of MCP121-450E/TO?

Compliance & Regulatory

Where can I find the MCP121-450E/TO datasheet?

What are equivalent replacements for MCP121-450E/TO?

Frequently Asked Questions

At what supply voltage does MCP121-450E/TO assert its reset output to protect a 5 V microcontroller?

Why would a designer choose a fixed-threshold reset IC like MCP121-450E/TO over an adjustable supervisor?

How does the TO-92 package of MCP121-450E/TO compare to SOT-23 reset ICs in a production assembly context?

Related Guides

CSD87313DMS Synchronous Buck Power Stage Design Guide

STEF05SGR eFuse Selection Guide for 5 V Overcurrent Protection

C0402C103K3RACTU Selection Guide: Choosing a 10 nF 0402 MLCC

STM32H753VIT6 MCU Selection Guide: Memory, Package, Connectivity, and Security

Why Buy from FindMyChip

About Microchip

More from Microchip

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