My Inquiry
My Account
Texas Instruments LP8551TLX/NOPB
- Part No.:
- LP8551TLX/NOPB
- Manufacturer:
- Texas Instruments
- Category:
- LED Drivers
- Package:
- 25-WFBGA, DSBGA
- Datasheet:
-
LP8551TLX/NOPB.pdf
- Description:
- IC LED DRV RGLTR PWM 25DSBGA
- Quantity:
- Payment:
- Shipping:
Inventory:1,393
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LP8551TLX/NOPB from Texas Instruments is a high-efficiency, four-channel white LED backlight driver IC with integrated 40-V boost converter, adaptive output voltage control, and I²C/PWM dual-brightness control. It delivers up to 50 mA per channel with ±3% current accuracy, supports 156–1250 kHz switching frequencies, and targets notebook LCD backlight systems requiring thermal de-rating and open/short LED fault detection.
For engineers reviewing the LP8551TLX/NOPB datasheet, LP8551TLX/NOPB pinout, LP8551TLX/NOPB application, or LP8551TLX/NOPB equivalent, key selection considerations include its DSBGA-25 package footprint, 2.7–22 V input range, programmable 8–13-bit PWM resolution, EEPROM-configurable thermal shutdown thresholds, and phase-shift PWM mode for audible-noise suppression in portable display power supplies.
Technical Context
The LP8551TLX/NOPB integrates a high-voltage DC/DC boost converter with adaptive output voltage control that dynamically tracks LED string forward voltage to minimize power loss. Its four independent current sinks support simultaneous brightness control via either hardware PWM input or I²C register writes, with internal 5–40 MHz PLL enabling selectable PWM resolution (8–13 bits) and frequency (600 Hz–19.2 kHz).
Functional safety includes real-time LED open/short fault detection on all four outputs, overtemperature protection with programmable trip points, and boost overcurrent/overvoltage shutdown. Internal EEPROM stores configuration data-including current setpoints, PWM frequency, phase-shift enable, and thermal slope-enabling minimal external component count and eliminating boot-time initialization overhead.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 2.7 V to 22 V - supports 1× to 5× Li-ion battery stacks without external LDO pre-regulation |
| Boost Output Voltage | Up to 40 V - sufficient for driving 10+ white LEDs in series at typical VF (~3.2 V) |
| LED Current Accuracy | ±3% - ensures consistent luminance across channels without per-channel calibration |
| Switching Frequency | 156 / 312 / 625 / 1250 kHz - selectable via EEPROM or RFSET resistor to optimize EMI vs. efficiency trade-off |
| PWM Resolution | 8–13 bits - enables smooth dimming down to 0.012% duty cycle (13-bit) for flicker-free user interface transitions |
| Thermal Protection | Programmable trip point (via EEPROM), 150°C shutdown - prevents thermal runaway during sustained high-brightness operation |
| Fault Detection | Open/short LED detection per channel + boost overcurrent/UVLO - provides system-level fault signaling via FAULT pin and I²C status register |
Pinout & Package
LP8551TLX/NOPB uses a 2.49 mm × 2.49 mm DSBGA-25 (YZR) package with 0.4-mm pitch, optimized for ultra-thin notebook PCBs and thermally constrained display modules.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A1, A2, B1, B2, D2, E4 | GND_SW / GND / GND_L | Dedicated ground returns for boost switch, signal logic, and LED sink paths - critical for minimizing noise coupling between power and analog domains |
| C1 | VIN | Main input supply (2.7–22 V); powers boost stage and internal LDO - requires local 10 μF ceramic decoupling |
| D1 | VLDO | Internal 5-V LDO output; can be externally bypassed or supplied in low-VIN (<5.5 V) configurations to maintain digital core voltage |
| A3 | EN | Active-high enable; controls full device startup/shutdown - must be pulled high for operation, compatible with 1.65–5 V logic |
| A4 | PWM | Analog PWM dimming input; accepts 0.1–25 kHz signals - internally measured for 13-bit duty cycle accuracy when BRT_MODE = 00/01 |
| B3 | ISET | Current-setting node; connects to RISET resistor (e.g., 16 kΩ → 23 mA max) - floating if EEPROM-only current control is used |
| B4 | FSET | PWM frequency-setting node; connects to RFSET resistor to select one of four fixed switching frequencies - disabled if EN_F_RES = 0 |
| C3 | FAULT | Open-drain fault indicator; asserts low on LED open/short, overtemperature, or boost overcurrent - requires external pull-up |
| C4 | VDDIO | Digital I/O reference (1.65–5 V); sets logic threshold for SDA/SCLK and FAULT - may tie to GND if PWM-only control is used |
| D3, D4 | SCLK, SDA | I²C interface pins; support 400 kHz standard-mode - require pull-ups to VDDIO and comply with TI's I²C timing specs (tSU:STA = 600 ns) |
| C5, D5, E3, E5 | OUT1–OUT4 | Four independent constant-current LED sinks; each capable of 50 mA with <105 mV saturation voltage at 20 mA - supports parallel string configurations |
Key Features
| Feature | Design Value |
|---|---|
| Adaptive Boost Voltage Control | Real-time FB monitoring adjusts VBOOST to minimum required level - reduces power loss by up to 30% versus fixed-output boost converters |
| Phase-Shift PWM (PSPWM) | Staggered turn-on of OUT1–OUT4 - lowers peak input current by >40%, enabling smaller input capacitors and eliminating audible coil whine |
| EEPROM Configuration Storage | Nonvolatile storage for 8+ parameters (current, PWM freq, thermal limits, slope) - eliminates host MCU initialization code and supports field reconfiguration |
| Thermal De-Rating with Programmable Slope | Gradual brightness reduction starting at user-defined temperature threshold - maintains display usability while preventing thermal shutdown |
| Integrated Fault Diagnostics | Dedicated FAULT pin + I²C status register reporting per-channel LED faults, boost OCP, UVLO, and junction overtemperature - simplifies system-level error handling |
Applications
| Notebook LCD Backlight | Tablet Display Power |
|---|---|
|
Use Scenario: Driving 4-string white LED array in 13.3-inch notebook display with 200–400 nits brightness and <1% flicker requirement. IC Role / Device Role / Timing Role: Primary LED current controller and boost power manager; regulates string current to ±3% matching and adapts VBOOST in <100 μs response time. Use Value: Enables single-chip solution replacing discrete boost + current-sink ICs, reducing BOM count by 7 components and PCB area by 28 mm². |
Use Scenario: Powering dual-zone edge-lit LED backlight in 10.1-inch Android tablet with dynamic local dimming via I²C command bursts. IC Role / Device Role / Timing Role: I²C-configurable current sink with 13-bit PWM resolution; executes brightness updates in <2 ms via register write + auto-slope ramp. Use Value: Supports seamless UI transitions and video playback without visible stepping, leveraging EEPROM-stored slope timing and phase-shift PWM. |
| Industrial Panel Display | Medical Imaging Monitor |
|
Use Scenario: Backlight for 15-inch sunlight-readable HMI panel operating continuously at 70°C ambient with strict MTBF requirements. IC Role / Device Role / Timing Role: Thermally robust LED driver with programmable 125°C de-rating threshold and open-circuit fault latching via FAULT pin. Use Value: Eliminates need for external thermal sensor and fault-handling logic, reducing design validation effort and improving long-term reliability. |
Use Scenario: DICOM-compliant diagnostic monitor requiring stable luminance (±0.5%) across 0–100% brightness range and zero audible noise during imaging. IC Role / Device Role / Timing Role: Precision current source with <0.5% matching and PSPWM mode - suppresses mechanical vibration in transformer cores and capacitors. Use Value: Meets IEC 62304 Class C software safety requirements by providing hardware-enforced fault containment and deterministic shutdown behavior. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LED backlight driver applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LP8552TLX/NOPB | Same DSBGA-25 package, identical pinout, but adds integrated 3.3-V LDO for MCU supply - increases quiescent current by 1.2 mA | Preferred when system lacks dedicated 3.3-V rail for display controller; not drop-in due to additional V33OUT pin function | Select LP8552TLX/NOPB only if auxiliary 3.3-V supply is required; otherwise LP8551TLX/NOPB offers lower IQ and identical backlight performance |
| TPS61165DRVR | Single-channel 40-V boost LED driver in WSON-10; no EEPROM, no I²C, no thermal de-rating - relies on external MCU for fault handling | Suitable for cost-sensitive single-string designs where firmware handles diagnostics; lacks multi-string synchronization and phase-shift capability | Choose TPS61165DRVR for simplified single-LED applications; LP8551TLX/NOPB remains superior for multi-string, noise-sensitive, or firmware-light systems |
Compared with LP8552TLX/NOPB, the LP8551TLX/NOPB provides identical LED drive performance with lower static power and no auxiliary LDO overhead; versus TPS61165DRVR, it delivers integrated diagnostics, multi-channel coordination, and hardware-based thermal management - making it optimal for premium portable displays.
Availability
LP8551TLX/NOPB is available at Aetrix Electronics and suitable for notebook backlight systems, industrial HMI panels, medical imaging monitors, and tablet display power supplies requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.
Supply support for LP8551TLX/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 over 50 years of innovation in energy-efficient power conversion and precision analog solutions.
The LP8551TLX/NOPB belongs to TI's LED backlight driver product line, engineered specifically for high-efficiency, low-noise, thermally robust LCD backlighting in space-constrained portable electronics - emphasizing integration, configurability, and system-level reliability.
FAQ
What is the maximum LED string voltage supported by the LP8551TLX/NOPB?
The LP8551TLX/NOPB supports up to 40 V on its OUT1–OUT4 pins and features a boost converter with 40-V maximum output voltage. This allows driving up to 12 white LEDs in series (assuming ~3.3 V VF per LED at 20 mA). The adaptive feedback loop continuously adjusts VBOOST to the minimum required level, ensuring efficient operation across varying LED forward voltages and temperature drift.
Does the LP8551TLX/NOPB require external programming before first use?
No, the LP8551TLX/NOPB ships with factory-programmed EEPROM defaults including 156-kHz switching frequency, 50-mA current limit, and default thermal thresholds. It operates immediately upon power-up with EN high and PWM or I²C control enabled. Custom configurations (e.g., higher PWM resolution or modified de-rating slope) can be written via I²C but are optional for basic functionality.
Can the LP8551TLX/NOPB drive more than four LED strings?
No, the LP8551TLX/NOPB has exactly four dedicated current-sink outputs (OUT1–OUT4) and no provision for external current mirror expansion. Each output is independently controllable via I²C or synchronized PWM, but adding more strings requires either paralleling outputs (not recommended due to matching degradation) or using multiple LP8551TLX/NOPB devices with synchronized PWM inputs.
How does the phase-shift PWM (PSPWM) mode reduce audible noise?
The LP8551TLX/NOPB's PSPWM mode staggers the turn-on timing of OUT1–OUT4 by fixed intervals, distributing the boost converter's input current demand across the PWM period. This reduces peak input current by up to 45%, lowering mechanical stress on inductors and ceramic capacitors - eliminating the 1–20 kHz coil whine common in non-phase-shifted LED drivers used in quiet environments like medical or premium consumer displays.
What happens when the FAULT pin asserts low on the LP8551TLX/NOPB?
When the FAULT pin goes low on the LP8551TLX/NOPB, it indicates one or more active faults: LED open/short on any output, boost overcurrent, input undervoltage (UVLO), or junction temperature exceeding the programmed threshold. The condition persists until the fault clears and the device completes its internal recovery sequence - typically requiring EN toggle or I²C clear-command. The corresponding fault flag remains set in the I²C status register for precise root-cause identification.
LP8551TLX/NOPB Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 25-WFBGA, DSBGA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- DC DC Regulator
- Topology:
- Step-Up (Boost)
- Internal Switch(s):
- Yes
- Number of Outputs:
- 4
- Voltage - Supply (Min):
- 2.7V
- Voltage - Supply (Max):
- 22V
- Voltage - Output:
- 40V
- Current - Output / Channel:
- 50mA
- Frequency:
- -
- Dimming:
- PWM
- Applications:
- Backlight
- Operating Temperature:
- -30°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 25-DSBGA
LP8551TLX/NOPB FAQ
1.How can I place an order for LP8551TLX/NOPB through Aetrix?
Please submit a Request for Quotation (RFQ) for LP8551TLX/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 LP8551TLX/NOPB reliable?
The price and inventory of LP8551TLX/NOPB are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LP8551TLX/NOPB is usually 5 days.
3.What payment methods are accepted for LP8551TLX/NOPB?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LP8551TLX/NOPB transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LP8551TLX/NOPB?
LP8551TLX/NOPB orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LP8551TLX/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 LP8551TLX/NOPB?
For technical support, including LP8551TLX/NOPB datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LP8551TLX/NOPB requirements.
6.How does Aetrix verify that LP8551TLX/NOPB is sourced from the original manufacturer or authorized distributors?
All LP8551TLX/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 LP8551TLX/NOPB meets industry standards.
7.What is the process for return or replacement of LP8551TLX/NOPB?
All LP8551TLX/NOPB units undergo pre-shipment inspection (PSI). If there is an issue with LP8551TLX/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 LP8551TLX/NOPB part is unused and in its original packaging.
Return procedure for LP8551TLX/NOPB:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LP8551TLX/NOPB Tags
-
BCR402RE6327HTSA1
Infineon Technologies
-
BCR430UXTSA2
Infineon Technologies
-
BCR420UE6433HTMA1
Infineon Technologies
-
BCR420UE6327HTSA1
Infineon Technologies
-
BCR421UE6327HTSA1
Infineon Technologies
-
LYT1604D-TL
Power Integrations
-
HV9910CLG-G
Microchip Technology
-
CL2N8-G
Microchip Technology
-
BCR420UW6-7
Diodes Incorporated
-
BCR421UW6-7
Diodes Incorporated
-
BCR420UFD-7
Diodes Incorporated
-
BCR421UFD-7
Diodes Incorporated
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…
