Texas Instruments LP5811AYBHR

Overview

LP5811AYBHR from Texas Instruments is a synchronous boost 4-channel RGBW LED driver with autonomous animation engine, designed for battery-powered portable electronics. It delivers precise constant-current sinking (0.1–51 mA per channel), operates from 0.5V to 5.5V input, supports 3V–5.5V programmable boost output, and achieves 95% efficiency at 4.2V_IN/5.0V_OUT/300mA - enabling stable LED brightness in earbuds, smartwatches, and VR headsets.

For engineers reviewing the LP5811AYBHR datasheet, LP5811AYBHR pinout, LP5811AYBHR application, or LP5811AYBHR equivalent, key selection considerations include its 12-pin DSBGA package, I²C-controlled analog+PWM dimming (up to 24 kHz), ultra-low 0.45 mA active current, integrated open/short detection, and autonomous lighting engine eliminating MCU real-time PWM generation.

Technical Context

The LP5811AYBHR integrates a synchronous boost converter with 140 mΩ high-side and 60 mΩ low-side MOSFETs, operating in adaptive constant-on-time valley-current mode (1 MHz PWM above 1.5 V_IN, down to 0.5 MHz below 1 V_IN). Its autonomous animation engine executes preloaded lighting sequences using internal 6 MHz clock synchronization across multiple devices.

Four independent constant-current sinks feature ≤±5% device-to-device and channel-to-channel error, 110 mV typical headroom at 25.5 mA, and configurable PWM phase shift. Logic pins support 1.8 V/3.3 V/5 V I/O, and true input-output disconnection occurs during shutdown (I_SD = 0.1 µA).

Key Specifications

Pinout & Package

LP5811AYBHR uses a 12-pin DSBGA (YBH) package measuring 1.84 mm × 1.43 mm with 0.4 mm pitch. The package supports fine-pitch PCB assembly for space-constrained wearables and earbuds.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 4-channel RGBW LED driver applications.

Compared with LP5811AYBHR, LP5811ADRRR offers superior thermal handling in power-dense designs but occupies 3.5× more PCB area, while LP5813AYBHR delivers 3× channel count in the same footprint-making both viable alternatives depending on thermal budget and LED count requirements.

Availability

LP5811AYBHR is available at Aetrix Electronics and suitable for portable electronics, wearable devices, and IoT edge nodes requiring stable component supply, extended battery life, and compact RGBW lighting control.

Supply support for LP5811AYBHR 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 and embedded processing technologies, with decades of expertise in power management and LED driver innovation.

The LP5811AYBHR belongs to TI's LP58xx family of autonomous LED drivers, engineered specifically for ultra-low-power, space-constrained consumer electronics where visual appeal and energy efficiency are co-primary design goals.

FAQ

What is the minimum input voltage required to start up the LP5811AYBHR?

The LP5811AYBHR requires a minimum of 1.8 V on VIN to initiate boost converter startup. Once operational, it sustains regulation down to 0.5 V input - enabling compatibility with deeply discharged single-cell batteries. Startup is controlled by the EN pin, which must exceed 1.2 V to enable the boost stage. Below 0.42 V, the device enters full shutdown with 0.1 µA quiescent current.

How does the LP5811AYBHR achieve audible-noise-free PWM dimming?

The LP5811AYBHR supports PWM dimming frequencies up to 24 kHz - well above the human hearing range (20 kHz) - eliminating coil whine and capacitor squeal. This is implemented via an integrated 8-bit PWM generator per channel, configurable for linear or exponential curves. The 24 kHz mode is selected using the pwm_fre register bit, and all four channels maintain synchronized timing when enabled.

Can the LP5811AYBHR drive LEDs directly from a 3.3 V supply without boosting?

Yes. When the configured VOUT setting is ≤ VIN, the LP5811AYBHR automatically enters pass-through mode, connecting VIN directly to VOUT with >95% efficiency. This avoids unnecessary boost conversion losses and preserves battery life in systems where input voltage meets LED forward voltage requirements - such as driving white LEDs from a regulated 3.3 V rail.

What protection features are integrated into the LP5811AYBHR?

The LP5811AYBHR includes LED open-circuit detection (70–220 mV threshold), LED short-circuit detection (32–68% of VOUT), overvoltage protection (5.5–5.9 V), thermal shutdown (150°C for LED driver, 155°C for boost), and undervoltage lockout (1.8 V rising, 0.4 V falling). These functions operate autonomously without MCU supervision, enhancing system robustness in unattended applications like video doorbells and wearables.

Is the LP5811AYBHR compatible with standard I²C buses operating at 400 kHz?

Yes. The LP5811AYBHR fully supports standard-mode (100 kHz), fast-mode (400 kHz), and fast-mode Plus (1 MHz) I²C protocols. Its SCL/SDA pins meet JEDEC JS-001 HBM ±4 kV ESD rating, and timing parameters (e.g., t_{SU_DAT} = 100 ns at 400 kHz) ensure reliable communication with common microcontrollers. Up to four LP5811AYBHR devices can share one bus using unique I²C addresses set by hardware pins.