My Inquiry
My Account
Texas Instruments LM2840XQMK/NOPB
- Part No.:
- LM2840XQMK/NOPB
- Manufacturer:
- Texas Instruments
- Package:
- SOT-23-6 Thin, TSOT-23-6
- Datasheet:
-
LM2840XQMK/NOPB.pdf
- Description:
- IC REG BUCK ADJ 100MA TSOT23-6
- Quantity:
- Payment:
- Shipping:
Inventory:700
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM2840XQMK/NOPB from Texas Instruments is a non-synchronous step-down DC/DC regulator in SOT-6L package, delivering up to 100 mA output current with 0.765-V feedback reference voltage, 550-kHz fixed switching frequency, and 4.5-V to 42-V input range-designed for battery-powered instrumentation requiring compact, efficient local regulation.
For engineers reviewing the LM2840XQMK/NOPB datasheet, LM2840XQMK/NOPB pinout, LM2840XQMK/NOPB application, or LM2840XQMK/NOPB equivalent, key selection criteria include input voltage range compatibility, feedback reference precision, shutdown quiescent current (16 µA), thermal shutdown threshold (175°C), and SOT-6L layout constraints for high-density PCBs.
Technical Context
The LM2840XQMK/NOPB implements current-mode PWM control with internal 0.9-Ω high-side MOSFET, fixed 550-kHz oscillator, and integrated soft-start via SHDN pin RC network. It features dedicated UVLO (3.7-V turn-on), gate-drive undervoltage lockout, and cycle-by-cycle current limiting calibrated to 525 mA typical.
Functional operation relies on external components: bootstrap capacitor (CB–SW), feedback divider (FB), Schottky diode (D1), and output inductor (L1). The device operates in continuous conduction mode at light loads and transitions to discontinuous mode under low-load conditions without compromising regulation stability.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 4.5 V to 42 V - supports wide-range industrial and automotive battery inputs without pre-regulation |
| Output Current | 100 mA max - sufficient for microcontrollers, sensors, and low-power logic rails |
| Feedback Reference | 0.765 V ±1.5% - enables precise adjustable output from 0.8 V to 36 V using resistor divider |
| Switching Frequency | 550 kHz - balances small external component size (e.g., 15-µH inductor) and EMI performance |
| Quiescent Current | 16 µA in shutdown - extends battery life in always-on monitoring systems |
| Thermal Shutdown | 175°C activation - protects against sustained overload or poor heatsinking in sealed enclosures |
| Current Limit | 525 mA typical - provides robust short-circuit protection while avoiding nuisance tripping during load transients |
Pinout & Package
SOT-6L (DDC) package: 1.60 mm × 2.90 mm, low-profile surface-mount, thermally enhanced with exposed pad (not electrically connected).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1: CB | Bootstrap bias supply | Connects to SW node via 0.15-µF ceramic capacitor to generate gate drive voltage for internal high-side FET |
| 2: GND | Power and signal ground | Primary return path for switch current, feedback, and shutdown circuits; must be low-impedance connection |
| 3: FB | Feedback input | Monitors output voltage via resistor divider; regulates VOUT = 0.765 V × (1 + R1/R2) |
| 4: SHDN | Logic-level enable/disable | Pull to GND for shutdown (16-µA IQ); pull ≥2.3 V to enable; must not float |
| 5: VIN | Main power input | Accepts 4.5–42 V; requires local 2.2-µF ceramic bypass capacitor between VIN and GND |
| 6: SW | Switch node output | Drives external inductor and Schottky diode; connects to CB capacitor and L1; high dv/dt node requiring careful routing |
Key Features
| Feature | Design Value |
|---|---|
| Internally compensated | Eliminates need for external compensation network-reduces BOM count and design iteration time |
| Soft-start via SHDN pin | RC-controlled ramp-up of current limit prevents inrush into capacitive loads without extra IC or circuitry |
| Short-circuit protected | Cycle-by-cycle current limiting responds within one switching period to prevent damage during output faults |
| Low RDS(ON) | 0.9 Ω typical - minimizes conduction loss and improves efficiency at 100-mA loads (85% typical @12 VIN/3.3 VOUT) |
| Thermal shutdown | Auto-recovery at 155°C - maintains safe operation under transient overloads without manual reset |
Applications
| Portable Hand-Held Instruments | Battery-Powered Equipment |
|---|---|
Use Scenario: Multifunction handheld meter powered by 9-V alkaline or Li-ion battery pack. IC Role / Device Role / Timing Role: Primary 3.3-V rail regulator stepping down variable battery voltage (6–42 V) to power MCU, ADC, and display driver. Use Value: 16-µA shutdown current extends shelf life; 550-kHz switching enables compact 15-µH inductor and avoids audible noise. | Use Scenario: Wireless sensor node with BLE radio and environmental sensors operating from two AA cells. IC Role / Device Role / Timing Role: Local 1.8-V or 3.3-V supply derived from 2.4–3.6-V battery input using adjustable feedback configuration. Use Value: 0.765-V reference allows accurate low-voltage outputs; SOT-6L footprint saves space on constrained PCBs. |
| Industrial Distributed Power | Portable Media Players |
Use Scenario: Field transmitter with 24-V loop-powered interface requiring isolated 5-V auxiliary rail. IC Role / Device Role / Timing Role: Secondary buck regulator accepting 18–42 V input from loop supply to generate stable 5-V logic rail. Use Value: 42-V absolute max input withstands surge transients; thermal shutdown ensures reliability in unventilated enclosures. | Use Scenario: MP3 player with Li-Po battery (3.0–4.2 V) and multiple voltage domains (core, I/O, audio). IC Role / Device Role / Timing Role: Efficient 1.2-V core supply generated from battery via adjustable output configuration. Use Value: Fixed 550-kHz frequency simplifies EMI filtering; low RDS(ON) sustains >80% efficiency across battery discharge curve. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar step-down regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM2841XQMK/NOPB | 300-mA output capability; identical pinout, package, and feature set | Supports higher-current loads (e.g., USB peripherals, larger displays) without redesign | Select when future-proofing for increased load or when sharing layout with LM2840XQMK/NOPB-based designs |
| TPS62840DRVR | 200-mA output, 1.8-V to 6.5-V input, 1.8-MHz switching, 25-nA shutdown IQ | Better suited for ultra-low-power coin-cell applications but incompatible input range and pinout | Choose only for new designs prioritizing nanowatt shutdown over wide-input flexibility |
Compared with LM2841XQMK/NOPB, the LM2840XQMK/NOPB trades output current headroom for tighter thermal margin in same footprint; versus TPS62840DRVR, it offers 42-V input tolerance and proven ruggedness in industrial environments but higher shutdown IQ.
Availability
LM2840XQMK/NOPB is available at Aetrix Electronics and suitable for portable instrumentation, battery-powered telemetry, and industrial distributed power applications requiring stable component supply across multi-year production cycles.
Supply support for LM2840XQMK/NOPB 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
Texas Instruments is a global semiconductor company headquartered in Dallas, Texas, delivering analog and embedded processing solutions for industrial, automotive, and personal electronics markets.
The LM284x family was designed as SIMPLE SWITCHER® regulators to simplify DC/DC buck converter implementation for engineers lacking power design expertise-emphasizing ease-of-use, minimal external components, and robust protection.
FAQ
What is the maximum input voltage rating for LM2840XQMK/NOPB?
The LM2840XQMK/NOPB has an absolute maximum input voltage rating of 45 V, with recommended operating range from 4.5 V to 42 V. Operation above 42 V may trigger internal UVLO shutdown or cause permanent damage if sustained. The 42-V upper limit ensures reliable performance across automotive battery transients and industrial 24-V/48-V systems.
Does LM2840XQMK/NOPB require external compensation components?
No, the LM2840XQMK/NOPB is internally compensated. Its control loop is factory-tuned for stability with standard external components (inductor, output capacitor, feedback resistors), eliminating the need for external compensation networks like Type II or III compensators. This reduces design complexity and board area while maintaining phase margin across temperature and load variations.
How does the SHDN pin function on LM2840XQMK/NOPB?
The SHDN pin on LM2840XQMK/NOPB is a logic-level enable input: pulling it below 0.3 V disables the regulator (IQ ≈ 16 µA), while driving it above 2.3 V enables normal operation. It must never be left floating. An RC network between SHDN and GND can implement programmable soft-start by modulating current limit during startup, preventing output overshoot and inrush into large capacitive loads.
What is the purpose of the CB pin on LM2840XQMK/NOPB?
The CB (Charge Bootstrap) pin on LM2840XQMK/NOPB supplies gate drive voltage to the internal high-side MOSFET. It must be connected to the SW node through a 0.15-µF or larger ceramic capacitor. During each switching cycle, this capacitor charges from VIN and provides the elevated voltage needed to fully enhance the internal FET, ensuring low RDS(ON) (0.9 Ω typical) and high efficiency across the input range.
Can LM2840XQMK/NOPB be used to generate sub-1-V outputs?
Yes, LM2840XQMK/NOPB can generate outputs below 1 V using its 0.765-V feedback reference. For example, a 0.8-V output is achieved with R1 = 30.9 Ω and R2 = 787 Ω per the formula VOUT = 0.765 V × (1 + R1/R2). Resistor values must stay within 100 Ω–10 kΩ to avoid bias current errors, and layout must minimize noise coupling to the FB node for stable low-voltage regulation.
LM2840XQMK/NOPB Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- SOT-23-6 Thin, TSOT-23-6
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Function:
- Step-Down
- Output Configuration:
- Positive
- Topology:
- Buck
- Output Type:
- Adjustable
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 4.5V
- Voltage - Input (Max):
- 42V
- Voltage - Output (Min/Fixed):
- 0.765V
- Voltage - Output (Max):
- 34V
- Current - Output:
- 100mA
- Frequency - Switching:
- 550kHz
- Synchronous Rectifier:
- No
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q100
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- TSOT-23-6
LM2840XQMK/NOPB FAQ
1.How can I place an order for LM2840XQMK/NOPB through Aetrix?
Please submit a Request for Quotation (RFQ) for LM2840XQMK/NOPB 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 LM2840XQMK/NOPB reliable?
The price and inventory of LM2840XQMK/NOPB are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM2840XQMK/NOPB is usually 5 days.
3.What payment methods are accepted for LM2840XQMK/NOPB?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM2840XQMK/NOPB transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM2840XQMK/NOPB?
LM2840XQMK/NOPB orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM2840XQMK/NOPB 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 LM2840XQMK/NOPB?
For technical support, including LM2840XQMK/NOPB datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM2840XQMK/NOPB requirements.
6.How does Aetrix verify that LM2840XQMK/NOPB is sourced from the original manufacturer or authorized distributors?
All LM2840XQMK/NOPB 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 LM2840XQMK/NOPB meets industry standards.
7.What is the process for return or replacement of LM2840XQMK/NOPB?
All LM2840XQMK/NOPB units undergo pre-shipment inspection (PSI). If there is an issue with LM2840XQMK/NOPB, 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 LM2840XQMK/NOPB part is unused and in its original packaging.
Return procedure for LM2840XQMK/NOPB:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM2840XQMK/NOPB 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
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…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
