My Inquiry
My Account
Microchip Technology MIC79050-4.2YS
- Part No.:
- MIC79050-4.2YS
- Manufacturer:
- Microchip Technology
- Category:
- Battery Chargers
- Package:
- TO-261-4, TO-261AA
- Datasheet:
-
MIC79050-4.2YS.pdf
- Description:
- IC BATT CHG LI-ION 1CEL SOT223-3
- Quantity:
- Payment:
- Shipping:
Inventory:3,086
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
MIC79050-4.2YS from Microchip Technology is a fixed-output 4.2 V linear lithium-ion battery charger IC in SOT-223 package, featuring ±0.75% battery voltage accuracy over –5°C to +60°C, 380 mV dropout at 500 mA, 10 µA reverse leakage, zero off-mode current, and thermal shutdown protection. It delivers precision constant-voltage charging for single-cell Li-ion batteries in space-constrained portable electronics.
For engineers reviewing the MIC79050-4.2YS datasheet, MIC79050-4.2YS pinout, MIC79050-4.2YS application, or MIC79050-4.2YS equivalent, key selection considerations include its 3-pin SOT-223 footprint, absence of enable/feedback pins, ultra-low quiescent ground current (≤3 µA in shutdown), 4.2 V ±0.75% regulation tolerance, and suitability for unregulated wall adapters with natural load-line current limiting.
Technical Context
The MIC79050-4.2YS implements a high-accuracy linear charging architecture using an integrated PNP pass transistor and bandgap reference. Its regulation loop maintains 4.2 V output with only 40 ppm/°C temperature coefficient and 0.05%/V line regulation, enabling stable termination voltage across input variations from +2.5 V to +16 V.
Unlike 8-lead variants, the MIC79050-4.2YS omits EN and FB pins-its operation is always enabled, and output voltage is factory-fixed. Protection functions include thermal shutdown triggered by die temperature exceeding +125°C and current-limiting that clamps output at ~750–1000 mA when BAT is shorted.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | Fixed 4.2 V ±0.75% over –5°C to +60°C - ensures Li-ion cell full-charge voltage stays within safe, energy-maximizing range. |
| Dropout Voltage | 380 mV typical at 500 mA - enables operation from low-headroom sources like 4.5 V wall adapters while maintaining regulation. |
| Reverse Leakage | 10 µA max - minimizes self-discharge when input is disconnected, critical for battery backup integrity. |
| Ground Current | ≤3 µA in shutdown - achieves true zero-off-mode current, eliminating standby drain in powered-down systems. |
| Input Voltage Range | +2.5 V to +16 V - supports wide-range unregulated inputs including 5 V USB, 9 V adapters, and 12 V industrial supplies. |
| Thermal Shutdown | Activates at +125°C junction temperature - prevents damage during sustained high-power dissipation or poor PCB heatsinking. |
| Operating Temp | –40°C to +125°C - rated for automotive cabin, industrial, and extended-temperature embedded environments. |
Pinout & Package
Package: SOT-223 (3-lead, thermally enhanced, with exposed tab connected to GND).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| IN (Pin 1) | Supply input | Accepts +2.5 V to +16 V unregulated or regulated source; feeds internal pass transistor base drive and bias circuitry. |
| BAT (Pin 3) | Battery output | Direct connection to Li-ion cell anode; delivers regulated 4.2 V and up to 500 mA continuous charge current. |
| GND (Pin 2 & Tab) | Ground reference and thermal path | Common return for all internal circuits; exposed metal tab provides primary thermal conduction to PCB copper plane. |
Key Features
| Feature | Design Value |
|---|---|
| ±0.75% voltage accuracy over Li-ion charging temp range | Maximizes usable battery capacity by holding termination voltage tightly within 4.2 V ±31.5 mV from –5°C to +60°C. |
| 380 mV dropout at 500 mA | Enables efficient charging from low-voltage sources (e.g., 4.5 V adapter) without requiring >5 V rails. |
| Zero off-mode current | Eliminates battery drain when input is removed-critical for self-charging battery packs left idle for months. |
| 10 µA reverse leakage | Prevents cell discharge through the IC when IN is floating or grounded, preserving state-of-charge during storage. |
| Thermal shutdown + current limit | Hardware-level protection against overtemperature and short-circuit faults without external components. |
Applications
| Cellular Phones | Palmtop Computers |
|---|---|
Use Scenario: Charging single-cell Li-ion battery from low-cost unregulated wall adapter with natural load-line impedance. IC Role / Device Role / Timing Role: Fixed 4.2 V linear charger providing constant-voltage termination after initial constant-current phase. Use Value: Eliminates need for external current-sense resistors or microcontroller-based charge management, reducing BOM count and layout area. | Use Scenario: Integrated battery charging in compact handheld computing devices with strict thermal and size constraints. IC Role / Device Role / Timing Role: Primary Li-ion charging regulator delivering precise 4.2 V termination with minimal external components (only input capacitor). Use Value: SOT-223 package enables direct mounting on small PCBs; 380 mV dropout allows use of 4.5 V input rails, simplifying power architecture. |
| Self-Charging Battery Packs | PDAs |
Use Scenario: Standalone rechargeable pack with built-in charger, powered via USB or proprietary adapter. IC Role / Device Role / Timing Role: Always-on linear charger ensuring accurate 4.2 V cutoff without enable control logic or firmware intervention. Use Value: Zero off-mode current preserves battery charge during long shelf life; 10 µA reverse leakage prevents parasitic drain when pack is disconnected. | Use Scenario: Legacy PDA designs requiring reliable, low-component-count Li-ion charging from variable-input wall adapters. IC Role / Device Role / Timing Role: Simple termination-stage charger completing CC/CV cycle initiated by external current-limited source. Use Value: ±0.75% voltage accuracy over –5°C to +60°C ensures consistent full-charge capacity across operating environments. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar lithium-ion battery charging applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MCP73831T-420I/OT | Single-cell Li-ion charger with integrated MOSFET, 4.2 V ±1% accuracy, 500 mA max, SOT-23-5 package; includes charge status pin and thermal regulation. | Requires external current-setting resistor; supports programmable charge current and end-of-charge indication. | Select MCP73831T-420I/OT when status feedback, adjustable current, or smaller SOT-23 footprint is required. |
| TP4056 | 4.2 V ±1% linear charger, 1 A max, SOP-8 package; includes battery temperature monitoring (NTC input) and pre-charge trickle mode. | Supports deep-discharge recovery (2.5 V start-up); adds safety features absent in MIC79050-4.2YS. | Choose TP4056 for cost-sensitive consumer applications needing full-featured charging with no external logic. |
Compared with MCP73831T-420I/OT and TP4056, the MIC79050-4.2YS offers superior voltage accuracy (±0.75% vs. ±1%) and lower reverse leakage (10 µA vs. ≥50 µA), but lacks charge status signaling and programmable current-making it optimal for fixed-current, minimal-BOM, high-precision termination-only roles.
Availability
MIC79050-4.2YS is available at Aetrix Electronics and suitable for cellular phones, palmtop computers, self-charging battery packs, and PDAs requiring stable component supply, long-lifecycle support, and guaranteed traceability for production programs.
Supply support for MIC79050-4.2YS includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Microchip Technology is a U.S.-based semiconductor company specializing in microcontrollers, analog devices, and power management ICs, with global manufacturing and quality certifications including ISO 9001 and AEC-Q200 for select products.
The MIC79050 product line delivers highly accurate, thermally robust linear Li-ion chargers targeting portable electronics where precision termination, minimal external components, and reliability under variable input conditions are critical.
FAQ
What is the output voltage tolerance of the MIC79050-4.2YS over temperature?
The MIC79050-4.2YS guarantees ±0.75% battery voltage accuracy over the Li-ion charging temperature range of –5°C to +60°C. This corresponds to a 4.2 V output varying no more than ±31.5 mV across that range, ensuring optimal cell capacity and longevity. The specification is validated per DS20005771B-page 3 Electrical Characteristics table.
Does the MIC79050-4.2YS have an enable pin?
No, the MIC79050-4.2YS does not include an enable (EN) pin. It is the 3-lead SOT-223 variant of the MIC79050 family and operates continuously whenever valid input voltage is applied to the IN pin. Enable functionality is only present on the 8-lead SOIC-8 (MIC79050-4.2YM) and MSOP-8 (MIC79050-4.2YMM) versions.
What is the maximum continuous output current of the MIC79050-4.2YS?
The MIC79050-4.2YS is rated for 500 mA continuous output current under specified thermal conditions. At this load, its typical dropout voltage is 380 mV. Exceeding 500 mA may trigger current-limit protection (~750–1000 mA threshold) or cause thermal shutdown if PCB heatsinking is insufficient, as detailed in DS20005771B-page 3.
Can the MIC79050-4.2YS be used with a 5 V USB power source?
Yes, the MIC79050-4.2YS supports input voltages from +2.5 V to +16 V, making 5 V USB fully compatible. With its 380 mV dropout at 500 mA, it maintains regulation even as USB voltage sags under load. However, ensure adequate PCB copper area for thermal dissipation-especially at higher currents-as outlined in DS20005771B-page 15 Thermal Considerations.
How does the MIC79050-4.2YS protect against reverse battery connection?
The MIC79050-4.2YS provides inherent reversed-battery protection: when the IN pin is disconnected or grounded while BAT remains at battery voltage, reverse current is limited to ≤12 µA (DS20005771B-page 10). This minimizes self-discharge and prevents damage, though it does not tolerate reverse polarity applied to the IN pin itself-external diode protection is recommended for such cases.
MIC79050-4.2YS Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- TO-261-4, TO-261AA
- Packaging:
- Tube
- Product Status:
- Active
- Battery Chemistry:
- Lithium Ion
- Number of Cells:
- 1
- Current - Charging:
- Constant, Pulsed
- Programmable Features:
- -
- Fault Protection:
- Over Current, Over Temperature, Reverse Battery, Reverse Current
- Charge Current - Max:
- -
- Battery Pack Voltage:
- 4.2V
- Voltage - Supply (Max):
- 16V
- Interface:
- -
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-223-3
MIC79050-4.2YS FAQ
1.How can I place an order for MIC79050-4.2YS through Aetrix?
Please submit a Request for Quotation (RFQ) for MIC79050-4.2YS on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for MIC79050-4.2YS reliable?
The price and inventory of MIC79050-4.2YS are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MIC79050-4.2YS is usually 5 days.
3.What payment methods are accepted for MIC79050-4.2YS?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MIC79050-4.2YS transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MIC79050-4.2YS?
MIC79050-4.2YS orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MIC79050-4.2YS order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for MIC79050-4.2YS?
For technical support, including MIC79050-4.2YS datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MIC79050-4.2YS requirements.
6.How does Aetrix verify that MIC79050-4.2YS is sourced from the original manufacturer or authorized distributors?
All MIC79050-4.2YS products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that MIC79050-4.2YS meets industry standards.
7.What is the process for return or replacement of MIC79050-4.2YS?
All MIC79050-4.2YS units undergo pre-shipment inspection (PSI). If there is an issue with MIC79050-4.2YS, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The MIC79050-4.2YS part is unused and in its original packaging.
Return procedure for MIC79050-4.2YS:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MIC79050-4.2YS Tags
-
BQ21040DBVR
Texas Instruments
-
MCP73812T-420I/OT
Microchip Technology
-
MCP73831T-2ACI/OT
Microchip Technology
-
MCP73832T-2ACI/OT
Microchip Technology
-
MCP73831T-2DCI/OT
Microchip Technology
-
MCP73832T-2DCI/OT
Microchip Technology
-
MCP73831T-2ATI/OT
Microchip Technology
-
MCP73832T-2ATI/OT
Microchip Technology
-
MCP73831T-5ACI/OT
Microchip Technology
-
MCP73832T-2ACI/MC
Microchip Technology
-
MCP73831T-2ACI/MC
Microchip Technology
-
MCP73831T-2ATI/MC
Microchip Technology
Tech Hub
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
