Texas Instruments TPS92511DDA

Overview

TPS92511DDA from Texas Instruments is a 65-V, 500-mA common-anode constant-current buck LED driver IC with integrated low-side N-channel MOSFET, no external current-sense resistor, and programmable switching frequency (50–500 kHz). It delivers ±3.6% LED current accuracy and supports PWM dimming with >1000:1 contrast ratio in architectural lighting and MR-16 LED lamps.

For engineers reviewing the TPS92511DDA datasheet, TPS92511DDA pinout, TPS92511DDA application, or TPS92511DDA equivalent, key selection considerations include its floating-buck topology enabling common-anode multi-string configurations, thermal foldback support via analog dimming, and SOIC-8 exposed-pad package optimized for high-voltage LED driver thermal management.

Technical Context

The TPS92511DDA employs a proprietary Pulse-Level-Modulation (PLM) control scheme operating in continuous conduction mode (CCM), regulating average LED current by sensing only the inductor current during the MOSFET on-time-not full-cycle current-enabling high accuracy (±3.6%) without external sensing resistors or loop compensation components. Its floating buck architecture uses an integrated low-side N-MOSFET (R_DS(on) = 1.4 Ω typ.) and eliminates bootstrapping requirements.

This architecture supports common-anode LED string interconnection across multiple channels with only n+1 inter-board wires instead of 2n, reducing wiring cost and complexity. The device features internal VCC regulation (5.4 V), programmable frequency via R_FS, and LED current setting via R_IADJ, all while maintaining operation across 4.5–65 V input range and –40°C to +125°C junction temperature.

Key Specifications

Pinout & Package

TPS92511DDA is housed in a Power Enhanced SOIC-8 package (HSOP-8) with 4.89 mm × 3.90 mm body and exposed thermal pad for direct PCB thermal coupling to ground plane.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar constant-current buck LED driver applications.

Compared with LM3409HVMM/NOPB and MPQ4425AGU-AEC1-P, the TPS92511DDA uniquely combines no-sense-resistor operation, common-anode topology support, and SOIC-8 thermal performance-making it optimal for cost-sensitive, thermally constrained, multi-string commercial lighting where BOM reduction and wiring simplification are critical.

Availability

TPS92511DDA is available at Aetrix Electronics and suitable for architectural lighting, office troffer, and MR-16 LED lamp designs requiring stable component supply, long-term production continuity, and consistent parametric performance across manufacturing lots.

Supply support for TPS92511DDA 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 LED driver innovation and high-reliability power conversion ICs.

The TPS92511DDA belongs to TI's high-voltage LED driver product line, engineered specifically for cost-effective, thermally efficient, and wiring-minimized constant-current solutions in commercial and industrial solid-state lighting applications.

FAQ

What is the maximum LED string voltage supported by the TPS92511DDA?

The TPS92511DDA does not specify a maximum LED string voltage directly, but its LX-to-PGND absolute maximum rating is 65 V, and recommended VIN range is 4.5–65 V. In practice, the maximum sustainable LED forward voltage equals VIN minus minimum dropout (determined by R_DS(on) × ILED and inductor DCR). For 500 mA operation at 65 V VIN, typical V_LED ≤ 60 V is safe. Always verify with worst-case R_DS(on) (2.15 Ω) and thermal conditions in your layout. The TPS92511DDA datasheet confirms operation with 38 V LED strings at 48 V input.

Does the TPS92511DDA require external loop compensation components?

No, the TPS92511DDA does not require external loop compensation components. Its proprietary Pulse-Level-Modulation (PLM) control architecture performs internal current regulation using only the inductor current waveform during the MOSFET on-time, eliminating the need for external compensation networks. This simplifies design, reduces component count, and improves stability across varying input voltages and LED forward voltages-key advantages confirmed in Section 7.3.1 of the TPS92511DDA datasheet.

Can the TPS92511DDA drive multiple LED strings in parallel?

The TPS92511DDA is designed for single LED string operation but supports multi-string systems via common-anode topology: multiple TPS92511DDA ICs can each drive one string with shared anode connection, eliminating per-string high-side sensing. This configuration requires only n+1 inter-board wires for n strings (vs. 2n conventionally). However, the TPS92511DDA itself does not provide active current balancing between strings-matching depends on LED binning and layout symmetry. Refer to Figure 15 in the TPS92511DDA datasheet for the validated common-anode implementation.

What is the purpose of the thermal pad on the TPS92511DDA package?

The exposed thermal pad on the TPS92511DDA's HSOP-8 package is electrically connected to PGND and serves as the primary heat dissipation path. It must be soldered to a large PCB copper pour tied to the system ground plane to maintain junction temperature within –40°C to +125°C limits. Thermal resistance data shows R_θJB = 30.6°C/W and R_θJCbot = 4.2°C/W-confirming that proper pad connection is essential for sustaining 500 mA continuous output. Omitting thermal pad connection risks thermal shutdown or reduced reliability, as stated in Section 6.4 of the TPS92511DDA datasheet.

How does the TPS92511DDA achieve 1000:1 PWM dimming contrast ratio?

The TPS92511DDA achieves >1000:1 PWM dimming contrast ratio through ultra-fast response: LED current begins conduction within nanoseconds of the DIM pin rising edge, with minimum controllable pulse width of 6 µs at 500 kHz switching frequency. At this frequency, a 150 Hz dimming signal yields 1000:1 ratio (1/150 s ÷ 6 µs ≈ 1111). This performance relies on the absence of control-loop delay inherent in PLM architecture and is validated in Figure 11 and Section 7.3.10 of the TPS92511DDA datasheet.