My Inquiry
My Account
Texas Instruments LM2840XMK-ADJL/NOPB
- Part No.:
- LM2840XMK-ADJL/NOPB
- Manufacturer:
- Texas Instruments
- Package:
- SOT-23-6 Thin, TSOT-23-6
- Datasheet:
-
LM2840XMK-ADJL/NOPB.pdf
- Description:
- IC REG BUCK ADJ 100MA TSOT23-6
- Quantity:
- Payment:
- Shipping:
Inventory:1,491
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM2840XMK-ADJL/NOPB from Texas Instruments is a non-synchronous PWM 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 compact, low-power battery-powered systems requiring stable 3.3-V or adjustable output.
For engineers reviewing the LM2840XMK-ADJL/NOPB datasheet, LM2840XMK-ADJL/NOPB pinout, LM2840XMK-ADJL/NOPB application, or LM2840XMK-ADJL/NOPB equivalent, key selection factors include its 16-µA shutdown quiescent current, internal 0.9-Ω high-side MOSFET, thermal/UVLO protection, soft-start via SHDN pin, and compatibility with ceramic input/output capacitors and Schottky diodes in space-constrained designs.
Technical Context
The LM2840XMK-ADJL/NOPB implements current-mode PWM control with an integrated high-side N-channel MOSFET and dedicated gate-drive bias (CB) circuitry. Its functional block includes error amplifier, bandgap reference, oscillator, PWM comparator, and cycle-by-cycle current limiting-enabling stable regulation across wide input voltage swings while maintaining tight output voltage accuracy via the 0.765-V FB reference.
It operates exclusively in continuous conduction mode (CCM) at fixed 550 kHz, with minimum on-time of 100 ns and maximum duty cycle of 94%. Protection features include thermal shutdown (engages at 175°C), input undervoltage lockout (UVLO turn-on at 3.7 V), and gate-drive UVLO-ensuring robust operation during start-up, overload, and transient conditions without external supervision.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 4.5 V to 42 V - supports direct connection to 12-V, 24-V, and 36-V industrial/battery rails without pre-regulation. |
| Output Current | Up to 100 mA - sufficient for powering microcontrollers, sensors, and low-power logic in portable instrumentation. |
| Feedback Reference Voltage | 0.765 V ±1.5% - enables precise adjustable output (e.g., 3.3 V, 5 V, 12 V) using standard resistor dividers with minimal bias current error. |
| Switching Frequency | 550 kHz - allows use of small 10–15 µH inductors and low-ESR ceramic capacitors for compact PCB layout. |
| Quiescent Current (Shutdown) | 16 µA typical - extends battery life in always-on or wake-on-event applications such as remote sensors. |
| High-Side MOSFET RDS(ON) | 0.9 Ω typical - minimizes conduction loss at light-to-moderate loads, supporting >85% efficiency at 100 mA output. |
| Protection Features | Thermal shutdown, input UVLO, gate-drive UVLO, short-circuit current limit - eliminates need for external fault management circuitry. |
Pinout & Package
SOT-6L (DDC) package, 1.60 mm × 2.90 mm body size, low-profile surface-mount construction optimized for thermal performance and automated assembly.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| CB | GATE BIAS SUPPLY | Provides bootstrap voltage for high-side MOSFET gate drive; requires 0.15-µF ceramic capacitor between CB and SW. |
| GND | GROUND REFERENCE | Power and signal ground return path; must be connected to low-impedance PCB plane for stability and EMI control. |
| FB | VOLTAGE FEEDBACK INPUT | Monitors output via resistor divider; regulates VOUT = 0.765 V × (1 + R1/R2); bias current <1 µA avoids divider loading. |
| SHDN | LOGIC-LEVEL ENABLE/DISABLE | Pull to GND to disable (16-µA IQ); pull ≥2.3 V to enable; tie to VIN if unused-must never float. |
| VIN | POWER INPUT | Accepts 4.5–42 V DC; requires local 2.2-µF ceramic bypass capacitor between VIN and GND. |
| SW | SWITCH NODE OUTPUT | Drives external inductor and Schottky diode; connects to CBOOT capacitor and power stage components. |
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 enables user-tailored inrush current limiting without extra ICs. |
| Small solution size | SOT-6L footprint plus discrete passives fits within <30 mm² total area-ideal for wearables and handheld tools. |
| Low shutdown IQ | 16-µA quiescent current preserves battery charge during system sleep modes in portable equipment. |
| Thermal and UVLO protection | Integrated safety circuits prevent damage during overtemperature, brownout, or startup faults-no external monitoring required. |
Applications
| Portable Hand-Held Instruments | Battery-Powered Equipment |
|---|---|
Use Scenario: Digital multimeter powered by two AA cells (2.4–3.2 V) with boost converter feeding LM2840XMK-ADJL/NOPB to generate stable 3.3-V rail for MCU and ADC. IC Role / Device Role / Timing Role: Primary step-down regulator providing regulated 3.3-V supply; handles input transients during battery swap and load steps. Use Value: 550-kHz switching enables compact 15-µH inductor and 22-µF ceramic output cap-reducing board area by >40% vs. lower-frequency alternatives. | Use Scenario: Wireless sensor node with Li-ion battery (3.0–4.2 V) and BLE SoC requiring clean 1.8-V and 3.3-V supplies. IC Role / Device Role / Timing Role: Adjustable buck regulator configured for 3.3-V output; supplies RF transceiver and digital core under dynamic load (10–100 mA). Use Value: 0.765-V FB reference and 16-µA shutdown IQ extend operational lifetime beyond 2 years on single 800-mAh cell. |
| Industrial Distributed Power | Portable Media Players |
Use Scenario: Field transmitter with 24-V loop-powered input conditioning 12-V auxiliary rail for analog front-end and HART modem. IC Role / Device Role / Timing Role: Input-tolerant buck converter stepping 24-V down to 12-V; withstands 42-V surges per IEC 61000-4-5. Use Value: 42-V absolute max input rating and thermal shutdown allow reliable operation in harsh industrial environments without derating. | Use Scenario: MP3 player with 3.7-V Li-Po battery generating 1.2-V core and 3.3-V I/O rails via dual-stage conversion. IC Role / Device Role / Timing Role: Second-stage buck regulator delivering 3.3-V to display driver and audio codec; operates at light load during playback pause. Use Value: 0.9-Ω RDS(ON) and current-mode control maintain >82% efficiency at 10 mA load-minimizing standby power loss. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar step-down regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM2841XMK-ADJL/NOPB | Higher 300-mA output current rating; identical pinout, FB voltage, and package. | Suitable where future load growth or margin is required-e.g., adding wireless connectivity to existing 100-mA design. | Select when peak load exceeds 100 mA but board space and bill-of-materials reuse are critical. |
| TPS62231DRVR | 3-MHz synchronous buck; 300-mA output; 0.6-V FB; smaller 2-mm × 2-mm WSON package. | Better suited for ultra-compact, high-efficiency applications where 550-kHz ripple is unacceptable. | Choose for space-constrained designs needing higher efficiency above 50 mA and faster transient response. |
Compared with LM2841XMK-ADJL/NOPB, the LM2840XMK-ADJL/NOPB offers tighter thermal budget and lower gate-drive complexity at reduced current capability; versus TPS62231DRVR, it provides higher input voltage tolerance and simpler external component requirements at the cost of switching frequency flexibility and synchronous rectification.
Availability
LM2840XMK-ADJL/NOPB is available at Aetrix Electronics and suitable for battery-powered equipment, portable hand-held instruments, and industrial distributed power applications requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.
Supply support for LM2840XMK-ADJL/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, specializing in analog, embedded processing, and power management technologies with broad industrial, automotive, and consumer market reach.
The LM284x family-including LM2840XMK-ADJL/NOPB-is part of TI's SIMPLE SWITCHER® portfolio, engineered for ease-of-use in cost-sensitive, space-constrained DC/DC conversion applications where reliability, wide input range, and minimal external components are prioritized.
FAQ
What is the maximum input voltage rating for LM2840XMK-ADJL/NOPB?
The LM2840XMK-ADJL/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 is not advised for sustained use, as it may trigger internal protection or reduce long-term reliability. The device's UVLO circuit ensures safe startup only when VIN exceeds 3.7 V.
Can LM2840XMK-ADJL/NOPB be used to generate a 1.8-V output?
Yes, LM2840XMK-ADJL/NOPB can generate 1.8 V using an external resistor divider on the FB pin. With a 0.765-V reference, setting R2 = 1.02 kΩ and R1 = 1.37 kΩ yields VOUT = 0.765 V × (1 + 1.37/1.02) ≈ 1.8 V. Resistor values must stay within 100 Ω–10 kΩ to avoid bias current errors, and layout should minimize FB trace noise.
Does LM2840XMK-ADJL/NOPB require an external Schottky diode?
Yes, LM2840XMK-ADJL/NOPB is a non-synchronous buck regulator and requires an external Schottky diode (e.g., MA2YD26) connected between SW and GND. The diode must have ≥25% higher breakdown voltage than max VIN (e.g., 50 V for 42-V input) and ≥100-mA average current rating; peak current handling must exceed 100 mA.
What is the purpose of the CB pin on LM2840XMK-ADJL/NOPB?
The CB pin on LM2840XMK-ADJL/NOPB supplies gate-drive bias voltage for the internal high-side MOSFET. It must be decoupled to the SW node via a 0.15-µF or larger ceramic capacitor (CBOOT). This bootstrap configuration enables efficient high-side switching without requiring a floating gate-driver supply, simplifying layout and reducing component count.
How does the SHDN pin function in LM2840XMK-ADJL/NOPB?
The SHDN pin on LM2840XMK-ADJL/NOPB controls device enable/disable: pulling below 0.3 V disables the regulator (IQ ≈ 16 µA), while pulling ≥2.3 V enables normal operation. It also supports analog soft-start-applying a ramped voltage (0–2.3 V) modulates current limit for controlled output rise time. If unused, tie directly to VIN; never leave floating.
LM2840XMK-ADJL/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:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- TSOT-23-6
LM2840XMK-ADJL/NOPB FAQ
1.How can I place an order for LM2840XMK-ADJL/NOPB through Aetrix?
Please submit a Request for Quotation (RFQ) for LM2840XMK-ADJL/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 LM2840XMK-ADJL/NOPB reliable?
The price and inventory of LM2840XMK-ADJL/NOPB are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM2840XMK-ADJL/NOPB is usually 5 days.
3.What payment methods are accepted for LM2840XMK-ADJL/NOPB?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM2840XMK-ADJL/NOPB transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM2840XMK-ADJL/NOPB?
LM2840XMK-ADJL/NOPB orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM2840XMK-ADJL/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 LM2840XMK-ADJL/NOPB?
For technical support, including LM2840XMK-ADJL/NOPB datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM2840XMK-ADJL/NOPB requirements.
6.How does Aetrix verify that LM2840XMK-ADJL/NOPB is sourced from the original manufacturer or authorized distributors?
All LM2840XMK-ADJL/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 LM2840XMK-ADJL/NOPB meets industry standards.
7.What is the process for return or replacement of LM2840XMK-ADJL/NOPB?
All LM2840XMK-ADJL/NOPB units undergo pre-shipment inspection (PSI). If there is an issue with LM2840XMK-ADJL/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 LM2840XMK-ADJL/NOPB part is unused and in its original packaging.
Return procedure for LM2840XMK-ADJL/NOPB:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM2840XMK-ADJL/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…
