My Inquiry
My Account
Texas Instruments LM3552SD/NOPB
- Part No.:
- LM3552SD/NOPB
- Manufacturer:
- Texas Instruments
- Category:
- LED Drivers
- Package:
- 14-WFDFN Exposed Pad
- Datasheet:
-
LM3552SD/NOPB.pdf
- Description:
- IC LED DRIVER RGLTR 1A 14WSON
- Quantity:
- Payment:
- Shipping:
Inventory:3,982
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM3552SD/NOPB from Texas Instruments is a fixed-frequency, current-mode step-up DC/DC white LED flash driver with dual integrated low-side NFETs (FET-T and FET-F), 1.25MHz switching frequency, 2.7–5.5V input range, and up to 1A total output current for high-power camera flash applications in mobile devices.
For engineers reviewing the LM3552SD/NOPB datasheet, LM3552SD/NOPB pinout, LM3552SD/NOPB application, or LM3552SD/NOPB equivalent, key selection considerations include torch/flash mode control via T/F pin, programmable flash timeout via external CFTO, independent enable (EN) logic, over-voltage protection (OVP) trip at 12.4V, and WSON-14 package thermal performance (θJA = 37.3°C/W).
Technical Context
The LM3552SD/NOPB implements a current-mode PWM boost converter architecture with internal error amplifier (gm = 135 µmho, AV = 135 V/V) and precision 1.265V feedback reference. It uses two dedicated low-side NFETs-FET-T (RDSON = 0.98Ω, ≤200mA continuous) and FET-F (RDSON = 0.36Ω, ≤500mA pulsed)-to separately regulate torch and flash LED currents.
Flash timeout is implemented via a 1.4µA current source charging external CFTO to a 1.16V trip threshold; OVP engages at 12.4V (typ.) and releases at 10.6V (typ.), while undervoltage lockout activates below 2.48V (typ.). Soft-start is controlled by ISS = 11.5µA charging CSS to VSS = 1.25V (typ.).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 2.7V to 5.5V - supports full Li-ion battery discharge curve without dropout. |
| Switching Frequency | 1.25MHz (typ.) - enables use of small 4.7µH inductors and low-ESR ceramic capacitors. |
| Feedback Reference | 1.265V (typ.) - tightly regulated voltage sets LED current via RT and RF resistors. |
| FET-T RDSON | 0.98Ω (typ.) - limits torch-mode power loss and thermal rise at ≤200mA continuous. |
| FET-F RDSON | 0.36Ω (typ.) - minimizes conduction loss during high-current flash pulses up to 1A total. |
| OVP Threshold | 12.4V (typ.) - protects LED, capacitor, and inductor during open-circuit or FB fault. |
| Flash Timeout Current | 1.4µA (typ.) - charges external CFTO to define precise flash duration (e.g., 1µF → ~860ms). |
Pinout & Package
LM3552SD/NOPB is housed in a 14-pin WSON package (4mm × 4mm, non-pullback, exposed die-attach pad) with θJA = 37.3°C/W. The exposed GND pad must be soldered for thermal and electrical integrity.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VIN | Input supply connection | Accepts 2.7–5.5V; powers internal circuitry and boost stage; requires ≥10µF low-ESR ceramic input cap. |
| EN | Enable logic input | High ≥1.2V enables operation; internal 1.2MΩ pull-down ensures safe shutdown when unconnected. |
| T/F | Torch/Flash mode selector | Low = torch mode (FET-T only); High = flash mode (FET-T + FET-F); no internal pull-up/down. |
| SW | Boost switch node | Connects to inductor and Schottky diode anode; withstands up to 20V; peak current limited to 2.1A. |
| FB | Current-sense feedback input | Monitors voltage across RT/RF to regulate LED current; bias current = 50nA; reference = 1.265V. |
| FET-T | Torch FET drain | Output node for continuous torch current path; RDSON = 0.98Ω; max continuous current ~200mA. |
| FET-F | Flash FET drain | Output node for pulsed flash current path; RDSON = 0.36Ω; enables additional ~500mA flash current. |
| FTO | Flash timeout timing input | Sinks 1.4µA to charge external CFTO; trip at 1.16V defines maximum flash pulse duration. |
| SS | Soft-start control | Sinks 11.5µA to charge external CSS; ramps internal reference to limit inrush current at startup. |
| OVP | Over-voltage protection sense | Ground to disable OVP (not recommended); otherwise monitors output for >12.4V fault condition. |
| GND / AGND | Analog and power ground | Pin 1, 7, and DAP are common GND; AGND (pin 6) must connect to GND via low-impedance trace. |
Key Features
| Feature | Design Value |
|---|---|
| Dual independent FET outputs | FET-T (0.98Ω) and FET-F (0.36Ω) enable separate, optimized current paths for torch (continuous) and flash (pulsed) modes. |
| Programmable flash timeout | External CFTO sets precise flash duration (e.g., 0.47µF → ~400ms); prevents LED damage from extended overdrive. |
| True load disconnect in shutdown | EN = low disconnects FB network and LED path from VIN, reducing shutdown current to ≤2.3µA. |
| Integrated OVP with auto-recovery | Shuts down SW FET at 12.4V and resumes at 10.6V, enabling safe pulsed operation during open-circuit faults. |
| 1.25MHz constant-frequency PWM | Enables predictable EMI filtering and compact BOM using 4.7µH inductor and 4.7–10µF MLCCs. |
Applications
| Smartphone Camera Flash | Digital Still Camera (DSC) Flash |
|---|---|
|
Use Scenario: Dual-mode illumination for smartphone rear/front cameras with rapid mode switching and thermal constraints. IC Role / Device Role / Timing Role: LM3552SD/NOPB acts as the primary flash LED driver, managing torch brightness and high-current flash pulses under baseband processor control via EN and T/F pins. Use Value: Delivers up to 1A peak flash current with <1µs mode transition, while soft-start and OVP protect LEDs and PCB layout during frequent use. |
Use Scenario: Compact, high-efficiency flash module in portable DSCs requiring consistent color temperature and minimal board area. IC Role / Device Role / Timing Role: LM3552SD/NOPB serves as the regulated boost driver for multi-die white LEDs, with FET-T/FET-F enabling calibrated torch preview and full-power flash capture. Use Value: Achieves >85% efficiency across 3.0–4.2V input range, minimizing heat buildup in sealed camera housings and extending battery life per shot. |
| PDA Camera Flash | Camcorder Torch Lamp |
|
Use Scenario: Low-profile flash solution for legacy PDA form factors with tight height budgets and single-cell Li-ion power. IC Role / Device Role / Timing Role: LM3552SD/NOPB provides regulated LED drive with integrated shutdown (EN) and torch/flash control (T/F), eliminating need for external MOSFETs or logic. Use Value: 4mm × 4mm WSON package fits narrow PCB edges; 2.3µA shutdown current preserves standby battery life over weeks. |
Use Scenario: Continuous, stable white-light illumination for handheld camcorders used in low-light video recording. IC Role / Device Role / Timing Role: LM3552SD/NOPB operates in torch mode (T/F = low) to deliver steady 200mA through high-brightness LEDs, with thermal shutdown protecting against prolonged use. Use Value: FET-T RDSON = 0.98Ω limits torch-mode power dissipation to <40mW, enabling passive cooling in plastic enclosures. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar white LED flash driver applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM3551SD/NOPB | Uses SD (shutdown) pin with internal 1.2MΩ pull-up to VIN; identical analog core, same pinout except SD replaces EN. | Preferred where system logic drives active-low enable signals; requires inverted control vs. LM3552SD/NOPB's active-high EN. | Select LM3551SD/NOPB only if existing firmware/hardware uses active-low enable; otherwise LM3552SD/NOPB offers simpler interface alignment. |
| TPS61310DSQR | Single-FET boost driver (no dual torch/flash FETs); 1.5A switch current limit; no integrated flash timeout or OVP auto-recovery. | Requires external FETs and timing circuitry for torch/flash separation; suited for custom timing or non-flash applications. | Choose TPS61310DSQR only when dual-FET integration is unnecessary and external control of timing/OVP is acceptable. |
Compared with LM3551SD/NOPB, LM3552SD/NOPB simplifies system-level enable logic with active-high EN; compared with TPS61310DSQR, it delivers turnkey flash functionality-including dual-FET control, programmable timeout, and OVP recovery-without external components.
Availability
LM3552SD/NOPB is available at Aetrix Electronics and suitable for smartphone camera flash, digital still camera (DSC) flash, and camcorder torch lamp applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.
Supply support for LM3552SD/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 specializing in analog, embedded processing, and power management ICs, with leadership in high-efficiency DC/DC conversion and LED driver innovation.
The LM3552SD/NOPB belongs to TI's white LED flash driver product line, designed specifically for space-constrained mobile imaging systems requiring integrated torch/flash control, robust fault protection, and minimal external component count.
FAQ
What is the function of the EN pin on the LM3552SD/NOPB?
The EN (Enable) pin on the LM3552SD/NOPB is an active-high logic input that controls device operation: applying ≥1.2V enables the IC, while ≤0.3V places it in shutdown mode. An internal 1.2MΩ pull-down resistor ensures default shutdown when the pin is left floating, enhancing system safety during power-up or reset sequences. This behavior distinguishes LM3552SD/NOPB from the pin-compatible LM3551SD/NOPB, which uses an active-low SD pin.
How does the LM3552SD/NOPB implement flash timeout protection?
The LM3552SD/NOPB implements flash timeout protection by sourcing a precise 1.4µA (typ.) current from the FTO pin to charge an external capacitor (CFTO). When the voltage across CFTO reaches 1.16V (typ.), the internal timeout circuit disables both FET-T and FET-F, turning off the LED. The part remains disabled until EN is pulled low and/or T/F is pulled low. For example, a 1µF capacitor yields ~860ms maximum flash duration, preventing LED thermal overstress.
Can the LM3552SD/NOPB drive multiple white LEDs in series?
No, the LM3552SD/NOPB is designed for parallel LED configurations using its dual low-side FETs (FET-T and FET-F) and single feedback node (FB). Its architecture regulates current through external resistors (RT and RF) tied to FET-T and FET-F, respectively-not voltage across a string. Driving series-connected LEDs would require reconfiguring the current-sense topology and violates the intended use case defined in the LM3552SD/NOPB datasheet and typical application circuits.
What is the maximum continuous current supported by the LM3552SD/NOPB in torch mode?
In torch mode (T/F = low), the LM3552SD/NOPB delivers current only through FET-T, which has an RDSON of 0.98Ω (typ.). Based on thermal limits and typical operating conditions (TA ≤ 85°C, proper PCB copper pour), the maximum recommended continuous current is 200mA. Exceeding this value risks exceeding the junction temperature limit (110°C) due to I²R losses, especially without adequate heatsinking via the exposed DAP.
Does the LM3552SD/NOPB require external compensation components?
Yes, the LM3552SD/NOPB requires external RC and CC components connected to the VC (compensation) pin to stabilize the voltage loop. A typical network uses RC = 10kΩ and CC = 4.7nF for Lumiled LEDs or RC = 27kΩ and CC = 10nF for Sharp LEDs. These values place a zero to cancel the output capacitor pole and ensure ≥45° phase margin; omitting or mis-sizing them can cause oscillation or poor transient response during LED current steps.
LM3552SD/NOPB Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 14-WFDFN Exposed Pad
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- DC DC Regulator
- Topology:
- Step-Up (Boost)
- Internal Switch(s):
- Yes
- Number of Outputs:
- 1
- Voltage - Supply (Min):
- 2.7V
- Voltage - Supply (Max):
- 5.5V
- Voltage - Output:
- -
- Current - Output / Channel:
- 1A (Flash)
- Frequency:
- 1.25MHz
- Dimming:
- -
- Applications:
- Camera Flash
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 14-WSON (4x4)
LM3552SD/NOPB FAQ
1.How can I place an order for LM3552SD/NOPB through Aetrix?
Please submit a Request for Quotation (RFQ) for LM3552SD/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 LM3552SD/NOPB reliable?
The price and inventory of LM3552SD/NOPB are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM3552SD/NOPB is usually 5 days.
3.What payment methods are accepted for LM3552SD/NOPB?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM3552SD/NOPB transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM3552SD/NOPB?
LM3552SD/NOPB orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM3552SD/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 LM3552SD/NOPB?
For technical support, including LM3552SD/NOPB datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM3552SD/NOPB requirements.
6.How does Aetrix verify that LM3552SD/NOPB is sourced from the original manufacturer or authorized distributors?
All LM3552SD/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 LM3552SD/NOPB meets industry standards.
7.What is the process for return or replacement of LM3552SD/NOPB?
All LM3552SD/NOPB units undergo pre-shipment inspection (PSI). If there is an issue with LM3552SD/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 LM3552SD/NOPB part is unused and in its original packaging.
Return procedure for LM3552SD/NOPB:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM3552SD/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…
