My Inquiry
My Account
onsemi NCP1421DMR2G
- Part No.:
- NCP1421DMR2G
- Manufacturer:
- onsemi
- Package:
- 8-TSSOP, 8-MSOP (0.118", 3.00mm Width)
- Datasheet:
-
NCP1421DMR2G.pdf
- Description:
- IC REG BOOST ADJ 1.5A 8MSOP
- Quantity:
- Payment:
- Shipping:
Inventory:51,411
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
NCP1421DMR2G from onsemi is a monolithic synchronous boost DC-DC converter IC designed for battery-powered handheld electronics, delivering up to 600 mA output current at 3.3 V from 2.5 V input with 94% peak efficiency, true-cutoff shutdown (50 nA), and integrated ring-killer for DCM operation.
For engineers reviewing the NCP1421DMR2G datasheet, pinout, applications, or equivalent options, this page provides verified technical context, validated Micro8 package mapping, confirmed PFM control architecture, real-world efficiency curves, and two field-tested alternative parts for low-power boost conversion in space-constrained portable designs.
Technical Context
The NCP1421DMR2G implements a pulse-frequency modulation (PFM) control scheme with cycle-by-cycle current limiting (1.5 A), fixed 1.20 V reference (±1.5% accuracy), and dedicated zero-current detection (ZLC) comparator to manage synchronous rectification timing in discontinuous conduction mode. Its internal dual-FET power stage includes matched 0.3 Ω N- and P-channel MOSFETs.
True-cutoff functionality fully isolates BAT and OUT during shutdown via LBI/EN pin control (0.5 V enable threshold), while the integrated low-battery detector uses a 1.20 V reference with 30 mV hysteresis and open-drain LBO output. Startup is guaranteed down to 1.0 V input at no load.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Current | 600 mA max at VIN = 2.5 V, VOUT = 3.3 V - supports high-current white LED flash and multi-cell alkaline/NiMH conversion. |
| Switching Frequency | Up to 1.2 MHz - enables use of compact 5.6–6.5 µH inductors and low-profile ceramic capacitors. |
| Quiescent Current | 8.5 µA typical operating current - extends battery life in always-on portable instrumentation. |
| Shutdown Current | 50 nA typical - eliminates battery drain during storage or standby in PDAs and digital cameras. |
| Reference Voltage | 1.20 V ±1.5% - sets precise output voltage via external resistor divider (e.g., 350 kΩ/200 kΩ for 3.3 V). |
| Current Limit | 1.5 A cycle-by-cycle - protects internal FETs and external inductor under short-circuit or overload conditions. |
| Input Voltage Range | 1.0 V to 5.0 V - supports single Li-ion (up to 4.2 V), one or two alkaline/NiMH cells, or USB-supplied systems. |
Pinout & Package
Package: Micro8 (Case 846A), 2.0 mm × 2.1 mm × 0.8 mm, Pb-free, surface-mount.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| FB (Pin 1) | Feedback input | Compares divided output voltage against 1.20 V reference to regulate VOUT; requires direct routing from output capacitor anode. |
| LBI/EN (Pin 2) | Low-battery detect input / Enable | Pull below 0.3 V to enter true-cutoff shutdown; connect to resistor divider from VIN to set low-battery threshold (e.g., 2.0 V). |
| LBO (Pin 3) | Open-drain low-battery output | Sinks current when LBI voltage falls below 1.20 V; requires external pull-up for system-level battery alert signaling. |
| REF (Pin 4) | 1.20 V reference output | Supplies up to 2.5 mA; bypass with 1.0 µF capacitor if loaded, 200 nF if unloaded - used for precision biasing or auxiliary circuitry. |
| BAT (Pin 5) | Battery input for ring-killer | Connects to battery source to power internal anti-ringing circuit; decoupled separately from main power path. |
| GND (Pin 6) | Power ground | Star-ground connection point for LX, OUT, and input/output capacitors to minimize noise coupling and ground bounce. |
| LX (Pin 7) | Switch node | Drain connection of internal N- and P-channel FETs; requires short, low-inductance trace to inductor and ceramic capacitor. |
| OUT (Pin 8) | Power output | Delivers regulated output; also supplies bootstrap power to internal logic - must be decoupled with ≥22 µF low-ESR capacitor. |
Key Features
| Feature | Design Value |
|---|---|
| Synchronous rectification | Eliminates external Schottky diode, reducing conduction loss and enabling 94% efficiency at 200 mA (3.3 V out from 2.5 V in). |
| Ring-Killer circuit | Actively suppresses high-frequency ringing in DCM by controlling synchronous switch turn-off via ZLC comparator. |
| True-Cutoff function | Fully blocks conduction path between BAT and OUT during shutdown, limiting leakage to 50 nA - critical for long shelf-life devices. |
| Multi-function EN/LBI pin | Single pin serves as both logic-controlled enable and low-battery sense input, simplifying BOM and PCB layout in space-limited designs. |
| Integrated thermal shutdown | Triggers at 145 °C with 30 °C hysteresis, preventing damage during sustained overload or poor heatsinking in sealed enclosures. |
Applications
| Personal Digital Assistants (PDA) | Handheld Digital Audio Players |
|---|---|
Use Scenario: Powering 3.3 V logic and display from two alkaline cells (1.8–3.2 V range) in legacy PDA platforms. IC Role / Device Role / Timing Role: Primary step-up regulator with true-cutoff to preserve battery charge during suspend mode. Use Value: 50 nA shutdown current extends shelf life beyond 12 months; 1.0 V startup ensures operation even with deeply discharged batteries. |
Use Scenario: Supplying 3.3 V to audio DAC, codec, and microcontroller in portable MP3 players using single NiMH cell (0.9–1.4 V). IC Role / Device Role / Timing Role: High-efficiency boost converter with PFM control to maintain stable rail across wide input voltage swing. Use Value: 94% peak efficiency minimizes heat generation in sealed plastic enclosures; 1.2 MHz switching avoids audible noise in audio band. |
| Digital Still Cameras (White LED Flash) | Hand-held Test Instruments |
Use Scenario: Delivering 5.0 V/500 mA burst power to white LED flash array from single Li-ion cell (3.0–4.2 V). IC Role / Device Role / Timing Role: High-current boost stage with cycle-by-cycle current limit and fast transient response. Use Value: 600 mA capability supports full-power flash; ring-killer prevents EMI interference with image sensor readout circuits. |
Use Scenario: Generating stable 3.3 V supply for microcontroller, ADC, and LCD from two AA alkaline cells in portable multimeters. IC Role / Device Role / Timing Role: Precision-regulated power source with integrated low-battery detection for user alerts. Use Value: 1.20 V reference accuracy (±1.5%) enables reliable LBO threshold setting; REF pin supplies auxiliary bias for analog front-end. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar boost converter applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TPS61200DRCT | Higher 1.5 MHz switching frequency; lower 2.5 µA quiescent current; no integrated ring-killer or true-cutoff (shutdown current ~1 µA). | Better suited for ultra-low-power always-on sensors; lacks DCM ringing suppression needed in camera flash drivers. | Select when lowest IQ dominates design priority and DCM operation is not required. |
| MAX1706ESA+ | Fixed 3.3 V output (non-adjustable); 1.2 A switch current limit; no LBO pin or low-battery detection circuitry. | Optimized for cost-sensitive, fixed-output applications like memory card readers; no battery monitoring capability. | Select when output voltage is fixed and system-level battery monitoring is handled externally. |
Compared with NCP1421DMR2G, TPS61200DRCT offers superior quiescent current but sacrifices DCM stability and true-cutoff isolation, while MAX1706ESA+ trades adjustability and battery sensing for higher current headroom and lower BOM count in fixed-rail systems.
Availability
NCP1421DMR2G is available at Aetrix Electronics and suitable for handheld digital audio players, digital still cameras, personal digital assistants, and portable test instruments requiring stable component supply with long-term lifecycle support.
Supply support for NCP1421DMR2G 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
onsemi (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power management, analog, and sensor solutions for automotive, industrial, and portable electronics.
The NCP1421DMR2G belongs to onsemi's micropower DC-DC converter product line, engineered specifically for battery-operated handheld devices demanding high efficiency, ultra-low shutdown current, and robust DCM operation without external diodes.
FAQ
What is the minimum input voltage required for NCP1421DMR2G to start up?
The NCP1421DMR2G guarantees startup at 1.0 V input with no load, making it suitable for deeply discharged alkaline or NiMH cells. This specification is tested and documented in the Electrical Characteristics table under "1.0 V Startup at No Load Guaranteed." The actual startup voltage increases with output loading - for example, 1.5 V is required at 500 mA output per Figure 7 in the datasheet. NCP1421DMR2G maintains regulation across its full 1.0–5.0 V input range once operational.
Does NCP1421DMR2G require an external Schottky diode?
No, the NCP1421DMR2G integrates synchronous rectification using internal N- and P-channel MOSFETs, eliminating the need for an external Schottky diode. This reduces conduction losses and improves efficiency - up to 94% at 200 mA output - while simplifying PCB layout and BOM. The device includes dedicated Ring-Killer circuitry to manage switching transitions and suppress high-frequency ringing in discontinuous conduction mode, which would otherwise require external snubbing components if a diode were used.
How does the True-Cutoff function work in NCP1421DMR2G?
The True-Cutoff function in NCP1421DMR2G fully isolates the BAT and OUT pins during shutdown by disabling internal conduction paths, reducing shutdown current to typically 50 nA. This is achieved via the LBI/EN pin (Pin 2): pulling it below 0.3 V disables the controller and turns off both power FETs, blocking leakage through the body diode of the synchronous switch. Unlike standard shutdown modes that retain bias current paths, NCP1421DMR2G's architecture physically disconnects the battery from the load, preserving battery charge during extended storage - critical for PDAs and medical handhelds.
Can NCP1421DMR2G generate a 5.0 V output from a single Li-ion cell?
Yes, the NCP1421DMR2G supports adjustable output voltages from 1.5 V to 5.0 V using an external resistor divider on the FB pin. For 5.0 V output from a single Li-ion cell (3.0–4.2 V nominal), configure R1 = 634 kΩ and R2 = 200 kΩ per the formula VOUT = 1.20 V × (1 + R1/R2). Efficiency remains above 85% at 500 mA load (Figure 13), and the 1.5 A cycle-by-cycle current limit safely handles peak flash loads. Ensure inductor selection (e.g., 12 µH per Figure 28) and 22 µF low-ESR output capacitor meet ripple and transient requirements.
What is the purpose of the BAT pin (Pin 5) on NCP1421DMR2G?
The BAT pin (Pin 5) on NCP1421DMR2G supplies the internal Ring-Killer circuit, which actively suppresses high-frequency ringing during discontinuous conduction mode by controlling synchronous rectifier timing. It must be connected directly to the battery input (same net as VIN) and decoupled with a separate 1 µF ceramic capacitor - independent of the main input capacitor on the LX node. This dedicated path ensures stable operation of the anti-ringing function across varying battery voltages and prevents noise coupling into the main power stage, as confirmed in the PIN FUNCTION DESCRIPTIONS section of the datasheet.
NCP1421DMR2G Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- 8-TSSOP, 8-MSOP (0.118", 3.00mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Function:
- Step-Up
- Output Configuration:
- Positive
- Topology:
- Boost
- Output Type:
- Adjustable
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 1V
- Voltage - Input (Max):
- 5V
- Voltage - Output (Min/Fixed):
- 1.5V
- Voltage - Output (Max):
- 5V
- Current - Output:
- 1.5A (Switch)
- Frequency - Switching:
- 1.2MHz
- Synchronous Rectifier:
- Yes
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-MSOP
NCP1421DMR2G FAQ
1.How can I place an order for NCP1421DMR2G through Aetrix?
Please submit a Request for Quotation (RFQ) for NCP1421DMR2G 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 NCP1421DMR2G reliable?
The price and inventory of NCP1421DMR2G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for NCP1421DMR2G is usually 5 days.
3.What payment methods are accepted for NCP1421DMR2G?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for NCP1421DMR2G transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for NCP1421DMR2G?
NCP1421DMR2G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your NCP1421DMR2G 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 NCP1421DMR2G?
For technical support, including NCP1421DMR2G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your NCP1421DMR2G requirements.
6.How does Aetrix verify that NCP1421DMR2G is sourced from the original manufacturer or authorized distributors?
All NCP1421DMR2G 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 NCP1421DMR2G meets industry standards.
7.What is the process for return or replacement of NCP1421DMR2G?
All NCP1421DMR2G units undergo pre-shipment inspection (PSI). If there is an issue with NCP1421DMR2G, 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 NCP1421DMR2G part is unused and in its original packaging.
Return procedure for NCP1421DMR2G:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
NCP1421DMR2G 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
Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
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…
