My Inquiry
My Account
Texas Instruments LM2611BMFX/NOPB
- Part No.:
- LM2611BMFX/NOPB
- Manufacturer:
- Texas Instruments
- Package:
- SC-74A, SOT-753
- Datasheet:
-
LM2611BMFX/NOPB.pdf
- Description:
- IC REG CUK ADJ 900MA SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:28,425
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM2611BMFX/NOPB from Texas Instruments is a current-mode PWM Cuk converter IC with integrated DMOS FET, designed for high-efficiency negative voltage generation. It operates from 2.7 V to 14 V input, delivers −5 V at 300 mA from 5-V input, features 1.4-MHz fixed switching frequency, 0.7-Ω RDS(ON), and 1-mVp-p output ripple-enabling compact bias supplies in portable imaging and display systems.
For engineers reviewing the LM2611BMFX/NOPB datasheet, LM2611BMFX/NOPB pinout, LM2611BMFX/NOPB application, or LM2611BMFX/NOPB equivalent, key selection criteria include its Grade B current limit (0.9 A), SOT-23-5 package footprint, NFB-based output voltage programming, and thermal shutdown behavior at 163°C junction temperature.
Technical Context
The LM2611BMFX/NOPB implements a fixed-frequency (1.4 MHz) current-mode control architecture with internal slope compensation and cycle-by-cycle overcurrent protection. Its functional block includes an integrated 0.7-Ω DMOS switch, 1.23-V precision reference, and dedicated NFB pin for external resistor-divider feedback-enabling stable regulation of inverted output voltages without external compensation components.
This Grade B variant supports input ranges up to 14 V and delivers regulated negative outputs via Cuk topology, leveraging separate input (L1) and output (L2) inductors to minimize RMS current and ripple on both sides. Shutdown functionality reduces quiescent current to <1 µA, and thermal shutdown activates at 163°C with hysteresis down to 155°C.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Switching frequency | 1.4 MHz typical; enables use of sub-22-µH inductors and ceramic capacitors under 10 µF for space-constrained designs. |
| Output voltage range | −(36 × VIN(MAX)) max; supports −5 V at 300 mA from 5-V input per typical application circuit. |
| RDS(ON) | 0.7 Ω typical (Grade B); reduces conduction loss and improves efficiency at medium load currents. |
| Current limit | 0.9 A typical (Grade B); sets maximum peak switch current, limiting output capability under low-VIN/high-VOUT conditions. |
| Quiescent current | 270 µA typical (enabled, no switching); drops to 0.024 µA in shutdown-critical for battery-powered standby operation. |
| NFB reference voltage | −1.23 V typical; defines output setpoint via external RFB1/RFB2 divider (e.g., 29.4 kΩ/10 kΩ for −5 V). |
| Thermal shutdown threshold | 163°C junction temperature; disables switch until die cools to 155°C-prevents permanent damage during sustained overload. |
Pinout & Package
LM2611BMFX/NOPB is housed in a 5-pin SOT-23 package (1.60 mm × 2.90 mm body size), optimized for surface-mount assembly and thermal dissipation via PCB copper area. Pin 2 (GND) serves as the common analog and power return path; thermal performance relies on proper board layout with adequate copper pour connected to GND.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 - SW | Drain of internal DMOS switch | Connects to node between input inductor (L1) and Cuk capacitor (CCUK); carries high di/dt switching current-requires short, low-inductance routing. |
| 2 - GND | Analog and power ground | Single-point return for feedback, reference, and power paths; must be tied directly to PCB ground plane with minimal impedance. |
| 3 - NFB | Negative feedback input | Accepts voltage divider from VOUT; internal 1.23-V reference compares against this node to regulate output polarity and magnitude. |
| 4 - SHDN | Shutdown control input | Logic-high (>1.5 V) enables operation; grounded (<0.5 V) forces device into ultra-low-IQ state-no external pull-up required. |
| 5 - VIN | Power input supply | Accepts 2.7–14 V; requires local 0.1-µF ceramic bypass capacitor placed ≤0.2 inches away to suppress high-frequency noise. |
Key Features
| Feature | Design Value |
|---|---|
| Cuk topology integration | Eliminates need for external controller, gate driver, and current-sense resistor-reduces BOM count and layout complexity for inverting supplies. |
| Low-RMS-current design | Input and output inductors (L1/L2) yield continuous triangular current waveforms-minimizing EMI and capacitor stress versus buck-boost alternatives. |
| Pulse-skipping mode | Automatically transitions from PWM to hysteretic operation below ~30 mA load-maintains regulation while reducing light-load switching losses. |
| Internal compensation | Fixed type-II/III network eliminates external compensation components; validated for 10–22 µH L1/L2 values-accelerates design cycle. |
| Feed-forward capacitor support | CFF across top feedback resistor (e.g., 330 pF) adds zero-pole pair to improve transient response bandwidth and phase margin. |
Applications
| MR Head Bias | Digital Camera CCD Bias |
|---|---|
Use Scenario: Precision negative bias for magneto-resistive read heads in HDD preamplifiers. IC Role / Device Role / Timing Role: Generates stable −5 V rail from 5-V system supply using Cuk topology to minimize noise coupling into sensitive analog front-end. Use Value: 1-mVp-p output ripple and low EMI ensure signal integrity in high-density storage channels. |
Use Scenario: High-stability negative bias for charge-coupled device (CCD) image sensors in portable cameras. IC Role / Device Role / Timing Role: Inverting regulator delivering −5 V at 300 mA with tight line/load regulation-critical for pixel charge transfer accuracy. Use Value: 1.4-MHz switching allows small 15-µH/47-µH inductors and 22-µF ceramics, enabling slim camera module form factors. |
| LCD Bias Supply | GaAs FET Bias |
Use Scenario: Negative gate drive for active-matrix LCD source drivers requiring −5 V to −10 V rails. IC Role / Device Role / Timing Role: Compact Cuk converter providing regulated negative voltage with fast transient response to dynamic display refresh cycles. Use Value: Pulse-skipping mode maintains regulation down to microamp loads during screen blanking-extending battery life. |
Use Scenario: Low-noise negative bias for gallium arsenide (GaAs) RF power amplifiers in wireless infrastructure. IC Role / Device Role / Timing Role: Delivers clean −5 V from 12-V intermediate bus with minimal conducted EMI-preserving amplifier linearity and gain flatness. Use Value: Integrated DMOS switch and internal compensation reduce component count and layout sensitivity versus discrete solutions. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar inverting DC-DC converter applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM2611AMFX/NOPB | Grade A variant: 1.2-A switch current limit, 0.5-Ω RDS(ON), higher output current capability at same VIN/VOUT. | Supports up to ~375 mA at −5 V from 12-V input; better suited for higher-power GaAs FET bias or multi-channel CCD arrays. | Select LM2611AMFX/NOPB when >300 mA output current or lower conduction loss is required; otherwise LM2611BMFX/NOPB offers cost-optimized performance. |
| TPS60403DBVR | Charge-pump inverter: no inductors, 600-kHz switching, 60-mA max output, ±1% initial accuracy, no NFB pin. | Limited to low-current applications (≤60 mA); lacks programmable output and inductor-based ripple suppression-unsuitable for MR head or CCD bias. | Choose TPS60403DBVR only for ultra-low-cost, ultra-small-footprint bias where current <60 mA and ripple <10 mVp-p is acceptable. |
Compared with LM2611AMFX/NOPB, the LM2611BMFX/NOPB trades 30% lower current limit and higher RDS(ON) for reduced cost and thermal stress in 300-mA applications; versus TPS60403DBVR, it provides 5× higher output current, inductor-based ripple reduction, and programmable output-but requires two external inductors.
Availability
LM2611BMFX/NOPB is available at Aetrix Electronics and suitable for MR head bias, digital camera CCD bias, and LCD panel bias applications requiring stable component supply, long-term industrial availability, and consistent parametric performance across production lots.
Supply support for LM2611BMFX/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 leader specializing in analog, embedded processing, and power management technologies, with decades of expertise in high-reliability power conversion ICs.
The LM2611 product line delivers integrated Cuk converter solutions for precision negative voltage generation in portable imaging, test equipment, and industrial sensing-designed to replace discrete inverter stages with minimal external components.
FAQ
What is the maximum output current capability of the LM2611BMFX/NOPB at −5 V from a 5-V input?
The LM2611BMFX/NOPB delivers up to 300 mA at −5 V when supplied from 5 V, as confirmed in the TI SNOS965J datasheet Figure 23 and Typical Application section. This rating assumes recommended 15-µH (L1) and 47-µH (L2) inductors, 22-µF ceramic output capacitor, and ambient temperature ≤85°C. Exceeding this current risks thermal shutdown due to the Grade B 0.9-A switch current limit.
How does the LM2611BMFX/NOPB differ from the LM2611AMFX/NOPB?
The LM2611BMFX/NOPB is the Grade B variant with 0.9-A typical switch current limit and 0.7-Ω RDS(ON), whereas LM2611AMFX/NOPB is Grade A with 1.2-A limit and 0.5-Ω RDS(ON). Both share identical pinout, package, reference voltage (−1.23 V), and 1.4-MHz switching frequency. The LM2611BMFX/NOPB is optimized for cost-sensitive 300-mA applications where the higher current capability of the A-grade is unnecessary.
Can the LM2611BMFX/NOPB generate output voltages other than −5 V?
Yes-the LM2611BMFX/NOPB uses resistor-divider feedback via the NFB pin to set output voltage. With its −1.23-V internal reference, any negative output can be programmed using RFB1 and RFB2 (e.g., −10 V with 58.8 kΩ/10 kΩ). The datasheet confirms operation down to −3.3 V and up to −(36 × VIN(MAX)), subject to inductor saturation and thermal limits.
What is the purpose of the CFF capacitor in LM2611BMFX/NOPB circuits?
The CFF capacitor (e.g., 330 pF) connects across the top feedback resistor (RFB1) in LM2611BMFX/NOPB designs to add a zero-pole pair that improves phase margin and transient response. As described in Section 7.3.6, this feed-forward network enhances stability under step-load changes-particularly critical in CCD and MR head bias applications where rapid current transients occur.
Does the LM2611BMFX/NOPB require external compensation components?
No-the LM2611BMFX/NOPB features fully internal type-II/III compensation optimized for 10–22 µH inductors, eliminating external compensation networks. TI's design validation ensures stability with standard Cuk configurations; however, adding CFF remains optional for enhanced transient performance. No external capacitor or resistor is needed for basic regulation.
LM2611BMFX/NOPB Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- SC-74A, SOT-753
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Function:
- Step-Up/Step-Down
- Output Configuration:
- Negative
- Topology:
- Cuk
- Output Type:
- Adjustable
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 2.7V
- Voltage - Input (Max):
- 14V
- Voltage - Output (Min/Fixed):
- -1.23V
- Voltage - Output (Max):
- -32V
- Current - Output:
- 900mA
- Frequency - Switching:
- 1.4MHz
- Synchronous Rectifier:
- No
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-5
LM2611BMFX/NOPB FAQ
1.How can I place an order for LM2611BMFX/NOPB through Aetrix?
Please submit a Request for Quotation (RFQ) for LM2611BMFX/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 LM2611BMFX/NOPB reliable?
The price and inventory of LM2611BMFX/NOPB are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM2611BMFX/NOPB is usually 5 days.
3.What payment methods are accepted for LM2611BMFX/NOPB?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM2611BMFX/NOPB transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM2611BMFX/NOPB?
LM2611BMFX/NOPB orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM2611BMFX/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 LM2611BMFX/NOPB?
For technical support, including LM2611BMFX/NOPB datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM2611BMFX/NOPB requirements.
6.How does Aetrix verify that LM2611BMFX/NOPB is sourced from the original manufacturer or authorized distributors?
All LM2611BMFX/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 LM2611BMFX/NOPB meets industry standards.
7.What is the process for return or replacement of LM2611BMFX/NOPB?
All LM2611BMFX/NOPB units undergo pre-shipment inspection (PSI). If there is an issue with LM2611BMFX/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 LM2611BMFX/NOPB part is unused and in its original packaging.
Return procedure for LM2611BMFX/NOPB:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM2611BMFX/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…
