My Inquiry
My Account
Texas Instruments LM2682MX/NOPB
- Part No.:
- LM2682MX/NOPB
- Manufacturer:
- Texas Instruments
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
LM2682MX/NOPB.pdf
- Description:
- IC REG CHARG PUMP INV 10MA 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:1,890
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM2682MX/NOPB from Texas Instruments is a CMOS switched-capacitor voltage inverter that converts +2.0 V to +5.5 V input into −4.0 V to −11.0 V negative output, delivers 10 mA load current, features 90 Ω typical output impedance, 94% typical power efficiency at 10 mA, and operates at 6 kHz switching frequency-used for LCD contrast biasing and GaAs amplifier supply in portable instrumentation.
For engineers reviewing the LM2682MX/NOPB datasheet, LM2682MX/NOPB pinout, LM2682MX/NOPB application, or LM2682MX/NOPB equivalent, this page provides verified technical context, package mapping, real-world use scenarios, and validated alternative options for low-noise negative rail generation in space-constrained battery-powered systems.
Technical Context
The LM2682MX/NOPB implements a two-stage charge-pump topology: first inverting VIN to −VIN, then doubling to −2VIN using three external capacitors. Its internal oscillator runs at 12 kHz (fOSC), driving switches at 6 kHz (fSW) with matched ON-resistance paths to minimize voltage drop.
Output regulation relies on passive capacitor network impedance rather than feedback control; output resistance (ROUT) is dominated by switch RON, capacitor ESR, and 1/(fOSC×C) terms-making low-ESR 3.3 μF capacitors critical for achieving ≤90 Ω at 5 V input and 10 mA load.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | +2.0 V to +5.5 V - supports single-cell Li-ion, dual-cell alkaline, and 3.3 V/5 V logic rails without level-shifting. |
| Output Voltage | −2 × VIN (e.g., −4.0 V to −11.0 V) - fixed inversion-doubling ratio enables predictable negative rail derivation. |
| Max Output Current | 10 mA - sufficient for biasing LCD segments, RF amplifiers, and analog interface ICs in handheld devices. |
| Switching Frequency | 6 kHz - low-frequency operation reduces EMI and allows use of low-cost ceramic capacitors without high-frequency derating. |
| Power Efficiency | 94% typical at 10 mA - minimizes quiescent current draw (150 μA no-load) to extend battery life in portable systems. |
| Output Impedance | 90 Ω typical - defines worst-case voltage droop (0.9 V at 10 mA), guiding capacitor selection for ripple and regulation targets. |
| Ambient Temp Range | −40°C to +85°C - qualified for industrial and extended commercial environments, not automotive or military. |
Pinout & Package
LM2682MX/NOPB is packaged in an 8-pin VSSOP (DGK) with 0.5 mm pitch, 3.0 mm × 3.0 mm body, and exposed pad for thermal relief. Pin 8 is NC; all other pins are electrically active and require correct capacitor routing per charge-pump phase timing.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (C1−) | C1 capacitor negative terminal | Connects to ground during Phase 1; forms pumping node with C1+ to store charge from VIN. |
| 2 (C2+) | C2 capacitor positive terminal | Connected to VOUT during Phase 2; transfers inverted/doubled charge to output node via C2−–GND path. |
| 3 (C2−) | C2 capacitor negative terminal | Switches between GND and VOUT; critical for polarity reversal and voltage doubling sequence. |
| 4 (VOUT) | Negative output voltage terminal | Delivers regulated −2VIN; requires low-ESR C3 (≥10 μF) to suppress ripple below 20 mVpp at 10 mA. |
| 5 (GND) | Device ground reference | Common return for all internal switches and external capacitors; must be low-impedance to avoid noise coupling. |
| 6 (VIN) | Positive input supply | Accepts 2.0–5.5 V; bypass with 0.1 μF ceramic near pin to stabilize internal oscillator and switch drivers. |
| 7 (C1+) | C1 capacitor positive terminal | Connected to VIN during Phase 1; charges C1 to VIN before transferring charge to C2 in Phase 2. |
| 8 (NC) | No connection | Unbonded die pad; must remain floating-no trace, solder mask opening, or thermal pad connection. |
Key Features
| Feature | Design Value |
|---|---|
| Voltage inversion + doubling | Generates precise −2VIN output without inductors-eliminates EMI, size, and cost penalties of magnetic-based converters. |
| Low quiescent current | 150 μA operating current enables >1-year battery life in always-on instrumentation with intermittent display usage. |
| Fixed 6 kHz switching | Enables predictable capacitor sizing and EMI filtering; avoids audible noise common with sub-20 kHz DC/DC converters. |
| VSSOP-8 package | 3.0 mm × 3.0 mm footprint saves >60% board area vs. SOIC-8, supporting ultra-compact PDAs and medical sensors. |
| Parallel operation support | Multiple LM2682MX/NOPB units can share one output capacitor to halve ROUT and double output current to 20 mA. |
Applications
| LCD Contrast Biasing | GaAs Power Amplifier Biasing |
|---|---|
|
Use Scenario: Generating adjustable negative bias voltage for STN/TN LCD segment drivers in handheld meters and barcode scanners. IC Role / Device Role / Timing Role: Charge-pump inverter providing stable −5 V rail from 3.3 V main supply to control LCD contrast ratio and viewing angle. Use Value: Eliminates need for external inductor and feedback circuitry-reducing BOM count by 4 parts and PCB area by 25 mm². |
Use Scenario: Supplying gate bias voltage for GaAs FET power amplifiers in UHF RFID readers and portable radios. IC Role / Device Role / Timing Role: Negative rail generator delivering −8 V at 5 mA to set amplifier quiescent point and optimize linearity. Use Value: Achieves <10 mVpp ripple with 10 μF/6.3 V X7R output capacitor-meeting GaAs PA noise floor requirements without LDO post-regulation. |
| Interface Power Supplies | Handheld Instrumentation |
|
Use Scenario: Providing isolated negative supply for RS-232 transceivers or op-amp signal conditioning stages in data loggers. IC Role / Device Role / Timing Role: Inverting doubler converting 5 V USB bus voltage to −10 V for true bipolar analog front-end operation. Use Value: Enables rail-to-rail input swing in instrumentation amplifiers without requiring dual ±12 V supplies or transformer-based isolation. |
Use Scenario: Powering analog sensor interfaces and display backlights in portable multimeters and thermal imagers. IC Role / Device Role / Timing Role: Compact negative rail source supporting simultaneous LCD bias and op-amp offset nulling from single 3.7 V Li-ion cell. Use Value: Delivers 94% efficiency at 10 mA-extending battery runtime by 22% compared to linear inverter solutions with same output capability. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar switched-capacitor inverter applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX680ESA+ | Fixed −5 V output (not adjustable); 100 Ω output impedance; 10 kHz switching; SO8 only. | Suitable only for fixed −5 V systems; lacks VIN-scaling flexibility of LM2682MX/NOPB's −2VIN output. | Select when system requires guaranteed −5 V (±2%) and board space permits SOIC-8; not for variable-input designs. |
| ICL7660SIPAZ | Wider input range (1.5–12 V); higher 120 Ω output impedance; 10 kHz switching; SO8 only. | Supports higher VIN but delivers lower efficiency (85% typ.) and higher dropout at 10 mA load. | Choose for legacy compatibility or 12 V input systems; avoid where >90% efficiency or VSSOP footprint is mandatory. |
Compared with MAX680ESA+ and ICL7660SIPAZ, LM2682MX/NOPB offers scalable −2VIN output, superior 94% efficiency at 10 mA, and space-saving VSSOP-8 packaging-making it optimal for modern portable instrumentation requiring flexible, high-efficiency negative rail generation.
Availability
LM2682MX/NOPB is available at Aetrix Electronics and suitable for LCD contrast biasing, GaAs amplifier biasing, and interface power supplies requiring stable component supply, RoHS-compliant packaging, and long-term industrial availability.
Supply support for LM2682MX/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, designing analog, embedded processing, and digital signal processing technologies since 1930.
LM2682MX/NOPB belongs to TI's precision switched-capacitor converter product line, engineered specifically for low-noise, inductorless negative rail generation in battery-powered portable electronics.
FAQ
What is the output voltage behavior of the LM2682MX/NOPB across its input range?
The LM2682MX/NOPB generates a precise −2 × VIN output: at VIN = 2.0 V, VOUT = −4.0 V; at VIN = 5.5 V, VOUT = −11.0 V. This fixed inversion-doubling ratio holds across the full −40°C to +85°C ambient temperature range and is independent of load up to 10 mA. No external feedback is required, and output voltage accuracy depends solely on capacitor ESR and layout parasitics-not internal trimming.
Can the LM2682MX/NOPB operate from a 3.3 V supply and deliver −6.6 V at 10 mA?
Yes-the LM2682MX/NOPB supports VIN = 3.3 V and will deliver −6.6 V nominal output at 10 mA load. With 90 Ω typical output impedance, expected voltage drop is 0.9 V, yielding −5.7 V under load. Using low-ESR 3.3 μF capacitors and minimizing PCB trace resistance ensures performance aligns with datasheet specifications for this condition.
What are the minimum recommended external capacitors for the LM2682MX/NOPB?
The LM2682MX/NOPB requires three external capacitors: C1 and C2 (3.3 μF, X7R, 6.3 V or higher rating), and C3 (≥10 μF, low-ESR tantalum or polymer, 16 V rating). C1 and C2 form the charge-transfer network; C3 filters output ripple. Using smaller values increases output impedance and ripple-e.g., 1 μF C3 raises P-P ripple from <20 mV to >100 mV at 10 mA.
Is the LM2682MX/NOPB pin-compatible with the LM2682MM/NOPB?
Yes-LM2682MX/NOPB and LM2682MM/NOPB share identical VSSOP-8 (DGK) package, pinout, and electrical specifications. The "X" suffix denotes tape-and-reel packaging (3500 pcs/reel), while "MM" denotes tube packaging (250 pcs/tube); both are functionally and mechanically interchangeable on PCBs designed for DGK footprint.
Does the LM2682MX/NOPB include overtemperature or short-circuit protection?
No-the LM2682MX/NOPB has no internal thermal shutdown or current limiting. It can sustain continuous VOUT short-circuit per Absolute Maximum Ratings, but junction temperature must remain ≤+125°C (operating) or ≤+150°C (absolute max). Designers must ensure θJA ≤ 220°C/W (VSSOP-8) and limit power dissipation using the formula PDissMAX = (TJMAX − TA)/θJA.
LM2682MX/NOPB Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Function:
- Ratiometric
- Output Configuration:
- Negative
- Topology:
- Charge Pump
- Output Type:
- Fixed
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 2V
- Voltage - Input (Max):
- 5.5V
- Voltage - Output (Min/Fixed):
- -Vin, 2Vin
- Voltage - Output (Max):
- -
- Current - Output:
- 10mA
- Frequency - Switching:
- 6kHz
- Synchronous Rectifier:
- No
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SOIC
LM2682MX/NOPB FAQ
1.How can I place an order for LM2682MX/NOPB through Aetrix?
Please submit a Request for Quotation (RFQ) for LM2682MX/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 LM2682MX/NOPB reliable?
The price and inventory of LM2682MX/NOPB are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM2682MX/NOPB is usually 5 days.
3.What payment methods are accepted for LM2682MX/NOPB?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM2682MX/NOPB transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM2682MX/NOPB?
LM2682MX/NOPB orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM2682MX/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 LM2682MX/NOPB?
For technical support, including LM2682MX/NOPB datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM2682MX/NOPB requirements.
6.How does Aetrix verify that LM2682MX/NOPB is sourced from the original manufacturer or authorized distributors?
All LM2682MX/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 LM2682MX/NOPB meets industry standards.
7.What is the process for return or replacement of LM2682MX/NOPB?
All LM2682MX/NOPB units undergo pre-shipment inspection (PSI). If there is an issue with LM2682MX/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 LM2682MX/NOPB part is unused and in its original packaging.
Return procedure for LM2682MX/NOPB:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM2682MX/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…
