Texas Instruments LM3533TME-40A/NOPB

Overview

LM3533TME-40A/NOPB from Texas Instruments is a fully integrated LED power management IC for smartphone backlight and indicator lighting. It drives two parallel high-voltage LED strings up to 40 V (HVLED1/HVLED2), five low-voltage current sinks (LVLED1–LVLED5) up to 30 mA each, and integrates a 2× charge pump, I²C interface, ambient light sensor (ALS) input, and PWM-controlled brightness adjustment. It operates from 2.7 V to 5.5 V and supports exponential dimming with 14-bit equivalent resolution.

For engineers reviewing the LM3533TME-40A/NOPB datasheet, LM3533TME-40A/NOPB pinout, LM3533TME-40A/NOPB application, or LM3533TME-40A/NOPB equivalent, this device delivers programmable dual-string boost + charge-pump LED driving in a space-constrained DSBGA package - critical for handset display, keypad, and RGB indicator subsystems requiring precise current matching, ALS-based auto-brightness, and pattern-driven blinking.

Technical Context

The LM3533TME-40A/NOPB implements a synchronous inductive boost converter (500 kHz / 1 MHz selectable) regulating HVLED1 and HVLED2 to 0.4 V headroom, while its integrated 2× charge pump powers LVLED1–LVLED5 with ≤2% current matching across temperature. It embeds an 8-bit ALS ADC with 128 programmable gain settings and internal low-pass filtering, enabling zone-based brightness mapping.

I²C-compatible configuration enables per-bank control (Control Banks A–F), independent pattern generation (4 engines), and flexible grouping of HV/LV current sinks. Overvoltage protection thresholds are configurable at 16 V, 24 V, 32 V, and 40 V via register bits, and thermal shutdown engages at 140°C with 15°C hysteresis.

Key Specifications

Pinout & Package

LM3533TME-40A/NOPB uses a 20-pin DSBGA (YFQ) package measuring 2.04 mm × 1.78 mm (27 mm² total solution size), optimized for ultra-thin mobile PCBs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LED driver applications.

Compared with LM3532TME-40A/NOPB, the LM3533TME-40A/NOPB integrates a charge pump to eliminate external bias rails for LVLEDs; versus TPS61165RTJR, it adds five programmable current sinks and ALS processing - making it uniquely suited for consolidated smartphone lighting subsystems.

Availability

LM3533TME-40A/NOPB is available at Aetrix Electronics and suitable for smartphone display backlighting, keypad illumination, and RGB indicator lighting requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for LM3533TME-40A/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 electronics.

The LM3533TME-40A/NOPB belongs to TI's lighting power management product line, designed specifically for space-constrained mobile devices requiring integrated high-voltage boost, low-voltage charge-pump LED driving, and intelligent ambient-light-responsive control.

FAQ

What is the maximum output voltage supported by the LM3533TME-40A/NOPB?

The LM3533TME-40A/NOPB supports a maximum output voltage of 40 V on its high-voltage boost converter, configurable via register-selectable overvoltage protection thresholds (16 V, 24 V, 32 V, or 40 V). This enables driving long series strings of white LEDs - up to 10–12 LEDs depending on forward voltage - while maintaining regulation headroom of 400 mV at HVLED1/HVLED2 terminals. The 40-V rating is validated across the full operating temperature range (−40°C to +85°C).

Does the LM3533TME-40A/NOPB require external components for the charge pump function?

Yes, the LM3533TME-40A/NOPB requires two external 1-µF ceramic capacitors for proper charge pump operation: one between C+ and C− pins (A2/A1), and another between CPOUT and GND (A3/B4). These capacitors are mandatory for stable 2× voltage multiplication and low-noise biasing of the five LVLED current sinks. Omitting or undersizing them results in excessive ripple, reduced current accuracy, and potential thermal stress on the internal charge pump circuitry.

How does ambient light sensing work on the LM3533TME-40A/NOPB?

The LM3533TME-40A/NOPB features a dedicated ALS pin (D2) that accepts either analog voltage (0–2.1 V) or PWM signals from external ambient light sensors. An internal 8-bit ADC digitizes the input, and firmware-configurable algorithms map the result to one of five brightness zones. Each zone points to a target current value assigned to specific control banks (A–F), enabling automatic LED brightness adjustment without host processor involvement - a key feature for battery-sensitive smartphone UIs.

Can the LM3533TME-40A/NOPB drive both display backlight and indicator LEDs simultaneously?

Yes, the LM3533TME-40A/NOPB is explicitly designed for concurrent operation: its integrated boost converter powers two high-voltage LED strings (HVLED1/HVLED2) for display backlight, while its 2× charge pump supplies five low-voltage current sinks (LVLED1–LVLED5) for keypad, status, or RGB indicators. All ten outputs are independently programmable via I²C, and can share ALS or PWM inputs for synchronized brightness control - eliminating the need for multiple discrete LED drivers in smartphone designs.

What package type and dimensions does the LM3533TME-40A/NOPB use?

The LM3533TME-40A/NOPB uses a 20-pin DSBGA (Die Size Ball Grid Array) package designated YFQ, with body dimensions of 2.04 mm × 1.78 mm and a maximum height of 0.67 mm. This wafer-level chip-scale package enables ultra-thin smartphone integration and requires microvia PCB routing. The pin pitch is 0.4 mm, and solder mask-defined pads are recommended per TI Application Note SNVA009 for reliable assembly yield.