My Inquiry
My Account
Microchip Technology MCP1603T-120I/OS
- Part No.:
- MCP1603T-120I/OS
- Manufacturer:
- Microchip Technology
- Package:
- SOT-23-5 Thin, TSOT-23-5
- Datasheet:
-
MCP1603T-120I/OS.pdf
- Description:
- IC REG BUCK 1.2V 500MA TSOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:3,461
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
MCP1603T-120I/OS from Microchip Technology is a fixed-output 1.2 V, 500 mA synchronous buck regulator optimized for single-cell Li-Ion and multi-cell NiMH/NiCd battery-powered portable electronics. It operates from 2.7 V to 5.5 V input, delivers >90% typical efficiency at full load, features 2.0 MHz PWM switching, and integrates P-channel and N-channel MOSFETs in a space-saving 5-lead TSOT package. Used in USB-powered devices and digital cameras for clean, low-noise 1.2 V rail generation.
For engineers reviewing the MCP1603T-120I/OS datasheet, MCP1603T-120I/OS pinout, MCP1603T-120I/OS application, or MCP1603T-120I/OS equivalent, key selection criteria include its fixed 1.2 V output, 45 µA PFM quiescent current, undervoltage lockout (2.28 V typ), thermal shutdown (150 °C), and compatibility with minimal external components (4.7 µF CIN/COUT, 4.7 µH inductor).
Technical Context
The MCP1603T-120I/OS implements a current-mode synchronous buck architecture with automatic PWM-to-PFM mode transition under light load to minimize quiescent current. Its internal 0.8 V reference and feedback loop enable precise 1.2 V regulation without external resistors.
It integrates cycle-by-cycle overcurrent protection (860 mA peak limit), undervoltage lockout with 140 mV hysteresis, and thermal shutdown with 10 °C hysteresis. The device supports 100% duty cycle operation and uses internally compensated control for stable performance with standard ceramic capacitors.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | Fixed 1.2 V ±2.5% over –40°C to +85°C; eliminates need for external feedback divider. |
| Max Output Current | 500 mA continuous; supports high-current portable logic rails like baseband processors. |
| Input Voltage Range | 2.7 V to 5.5 V; compatible with 1-cell Li-Ion (2.7–4.2 V) and 3-cell NiMH (3.6–4.5 V) sources. |
| Quiescent Current (PFM) | 45 µA typical; extends battery life in standby modes of handheld devices. |
| Switching Frequency | 2.0 MHz typical; enables use of small 4.7 µH inductors and 4.7 µF ceramic capacitors. |
| Efficiency | >90% typical at 100–500 mA load (VIN = 3.6 V, VOUT = 1.2 V); reduces thermal load in compact enclosures. |
| UVLO Threshold | 2.28 V typical with 140 mV hysteresis; prevents erratic startup during battery sag. |
| Thermal Shutdown | 150 °C junction temperature with 10 °C hysteresis; protects against sustained overload or poor PCB cooling. |
Pinout & Package
Package: 5-lead TSOT-23 (MCP1603 variant), 0.95 mm profile, exposed pad not present - distinct from DFN variant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1: VIN | Power supply input | Accepts 2.7–5.5 V; requires local 4.7 µF ceramic decoupling to GND for EMI suppression. |
| 2: GND | Ground reference | Primary return path for power and control circuits; must be low-inductance connection to system ground plane. |
| 3: SHDN | Enable/disable control | Logic-high (>45% VIN) enables regulator; logic-low (<15% VIN) disables with 0.1 µA shutdown current. |
| 4: VFB/VOUT | Feedback / output sense | Connected directly to regulated 1.2 V output; internal 0.8 V reference sets fixed voltage via internal resistor ratio. |
| 5: LX | Switch node | Drives buck inductor; carries high di/dt current - requires shortest possible trace to minimize EMI and voltage spikes. |
Key Features
| Feature | Design Value |
|---|---|
| Integrated Synchronous MOSFETs | P-channel high-side and N-channel low-side switches eliminate external diode, improving efficiency by ~5–10% vs. asynchronous designs. |
| Automatic PWM/PFM Transition | Seamlessly shifts from 2.0 MHz PWM (heavy load) to pulse-skipping PFM (light load), maintaining >85% efficiency down to 1 mA output. |
| Internally Compensated Control Loop | Enables stable regulation with only 4.7 µF input/output ceramics and 4.7 µH inductor - no external compensation network required. |
| Undervoltage Lockout + Hysteresis | Prevents brown-out oscillation during battery discharge; 140 mV hysteresis ensures clean re-start after recovery. |
| Overtemperature Protection | Shuts down at 150 °C junction temperature and auto-restarts at 140 °C, protecting against thermal runaway in sealed enclosures. |
| Low-Profile TSOT-23 Packaging | 5-pin, 2.9 × 1.6 × 0.95 mm footprint saves board area in space-constrained portable PCBs. |
Applications
| Portable Medical Sensors | Digital Audio Players |
|---|---|
Use Scenario: Powering ultra-low-power glucose monitors and pulse oximeters from coin-cell or Li-Poly batteries. IC Role / Device Role / Timing Role: Primary 1.2 V supply for ARM Cortex-M0+ microcontroller and analog front-end ADC. Use Value: 45 µA PFM quiescent current extends battery life to >12 months in sleep mode; 1.2 V output matches core voltage requirements of modern low-voltage MCUs. |
Use Scenario: Generating clean 1.2 V core rail for audio CODECs and flash memory controllers in MP3 players. IC Role / Device Role / Timing Role: Synchronous buck converter delivering regulated 1.2 V at up to 500 mA with <15 mV ripple. Use Value: 2.0 MHz switching avoids audible noise in audio band; >90% efficiency minimizes heat near sensitive analog circuitry. |
| USB-Powered Test Instruments | Industrial Handheld Scanners |
Use Scenario: Converting 5 V USB power to 1.2 V for FPGA configuration and sensor interface ICs in field calibration tools. IC Role / Device Role / Timing Role: Fixed-output DC-DC regulator enabling plug-and-play operation without external feedback tuning. Use Value: Fixed 1.2 V option eliminates resistor tolerance errors and layout sensitivity; 5-lead TSOT simplifies routing on dense 4-layer boards. |
Use Scenario: Supplying 1.2 V to barcode image sensors and Bluetooth SoCs in ruggedized warehouse scanners. IC Role / Device Role / Timing Role: Main power stage supporting intermittent 400 mA bursts during scan cycles while maintaining regulation across 2.7–5.5 V input range. Use Value: UVLO (2.28 V) and thermal shutdown ensure reliable operation during extended use in hot environments; 500 mA rating handles peak sensor + radio loads. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar synchronous buck regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TPS62231DRYR | 1.2 V fixed, 600 mA, 3.0 MHz switching, 17 µA quiescent current (PWM-only), 6-pin WSON. | Higher frequency allows smaller LC components but lacks PFM mode; unsuitable for ultra-low-power sleep states. | Select when board space is critical and minimum load >5 mA is guaranteed; avoid where battery standby life is primary concern. |
| RT8059GJ6 | 1.2 V fixed, 500 mA, 1.5 MHz, 25 µA quiescent current (PFM), 6-pin SOT-23-6, no integrated low-side FET. | Asynchronous design requires external Schottky diode; lower efficiency (~5% less) and higher thermal stress at full load. | Choose only if cost is overriding factor and 500 mA continuous load is rare; verify diode thermal derating in enclosure. |
Compared with TPS62231DRYR and RT8059GJ6, the MCP1603T-120I/OS uniquely balances ultra-low PFM quiescent current (45 µA), integrated synchronous switches, and proven reliability in battery-critical portable systems - making it optimal for long-life, space-constrained, single-cell applications demanding both efficiency and simplicity.
Availability
MCP1603T-120I/OS is available at Aetrix Electronics and suitable for portable medical sensors, digital audio players, USB-powered test instruments, and industrial handheld scanners requiring stable component supply and long-term manufacturability.
Supply support for MCP1603T-120I/OS 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 a focus on embedded control and energy-efficient solutions.
The MCP1603/B/L family was designed specifically for high-efficiency, low-quiescent-current DC-DC conversion in battery-powered portable electronics - emphasizing integration, small footprint, and robust protection features for consumer and industrial handheld applications.
FAQ
What is the output voltage tolerance of the MCP1603T-120I/OS over temperature?
The MCP1603T-120I/OS maintains a fixed 1.2 V output with ±2.5% tolerance over the full operating temperature range of –40°C to +85°C. This specification is verified per Microchip DS22042B, Section 1.0 Electrical Characteristics, and reflects the combined effect of internal reference drift and feedback network accuracy - ensuring reliable core voltage delivery to low-voltage logic without external trimming.
Does the MCP1603T-120I/OS require external compensation components?
No, the MCP1603T-120I/OS is internally compensated and operates stably with only three external components: a 4.7 µF input capacitor, a 4.7 µF output capacitor, and a 4.7 µH inductor. This eliminates the need for external RC networks or loop compensation adjustments, reducing design time and component count - a key advantage confirmed in the Typical Application Circuit on DS22042B-page 2.
Can the MCP1603T-120I/OS operate with a 2.5 V input voltage?
Yes, the MCP1603T-120I/OS supports input voltages as low as 2.7 V per its Absolute Maximum Ratings and DC Characteristics tables. A 2.5 V input falls below the specified 2.7 V minimum and will trigger undervoltage lockout (UVLO), preventing regulation. Operation requires VIN ≥ 2.7 V - consistent with 1-cell Li-Ion minimum discharge voltage.
What is the purpose of the SHDN pin on the MCP1603T-120I/OS?
The SHDN pin on the MCP1603T-120I/OS provides logic-level enable/disable control: a voltage >45% of VIN enables regulation, while <15% of VIN disables the device, reducing input current to 0.1 µA typical. This pin supports system-level power sequencing and deep-sleep modes - critical for extending battery life in portable devices using the MCP1603T-120I/OS.
Is the MCP1603T-120I/OS pin-compatible with other variants in the MCP1603/B/L family?
The MCP1603T-120I/OS uses the 5-lead TSOT-23 package with pinout matching the MCP1603/MCP1603B variants (VIN, GND, SHDN, VFB/VOUT, LX). However, it is not pin-compatible with the 8-lead DFN variant (MCP1603) due to differing pin count, layout, and NC/EP terminals - PCB layout must match the specific TSOT-23 footprint defined in DS22042B-page 2.
MCP1603T-120I/OS Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- SOT-23-5 Thin, TSOT-23-5
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Function:
- Step-Down
- Output Configuration:
- Positive
- Topology:
- Buck
- Output Type:
- Fixed
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 2.7V
- Voltage - Input (Max):
- 5.5V
- Voltage - Output (Min/Fixed):
- 1.2V
- Voltage - Output (Max):
- -
- Current - Output:
- 500mA
- Frequency - Switching:
- 2MHz
- Synchronous Rectifier:
- Yes
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- TSOT-23-5
MCP1603T-120I/OS FAQ
1.How can I place an order for MCP1603T-120I/OS through Aetrix?
Please submit a Request for Quotation (RFQ) for MCP1603T-120I/OS 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 MCP1603T-120I/OS reliable?
The price and inventory of MCP1603T-120I/OS are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MCP1603T-120I/OS is usually 5 days.
3.What payment methods are accepted for MCP1603T-120I/OS?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MCP1603T-120I/OS transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MCP1603T-120I/OS?
MCP1603T-120I/OS orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MCP1603T-120I/OS 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 MCP1603T-120I/OS?
For technical support, including MCP1603T-120I/OS datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MCP1603T-120I/OS requirements.
6.How does Aetrix verify that MCP1603T-120I/OS is sourced from the original manufacturer or authorized distributors?
All MCP1603T-120I/OS 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 MCP1603T-120I/OS meets industry standards.
7.What is the process for return or replacement of MCP1603T-120I/OS?
All MCP1603T-120I/OS units undergo pre-shipment inspection (PSI). If there is an issue with MCP1603T-120I/OS, 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 MCP1603T-120I/OS part is unused and in its original packaging.
Return procedure for MCP1603T-120I/OS:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MCP1603T-120I/OS Tags
-
TPS562201DDCR
Texas Instruments
-
MC34063ABD-TR
STMicroelectronics
-
TPS561201DDCR
Texas Instruments
-
MC33063ADR
Texas Instruments
-
MC34063ADR
Texas Instruments
-
TPS560200DBVR
Texas Instruments
-
AP3012KTR-G1
Diodes Incorporated
-
TLV61048DBVR
Texas Instruments
-
AZ34063UMTR-G1
Diodes Incorporated
-
TPS562200DDCR
Texas Instruments
-
AP62300TWU-7
Diodes Incorporated
-
MC34063EBD-TR
STMicroelectronics
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…
