Texas Instruments

The LM3537 is a highly integrated LED driver capable of driving 8 LEDs in parallel for single display backlighting applications. Independent LED control allows for a subset of the main display LEDs to be selected for partial illumination applications. I2C-compatible control allows full configurability of the backlighting function. The LM3537 provides multi-zone Ambient Light Sensing allowing autonomous backlight intensity control in the event of changing ambient light conditions. A PWM input is also provided to give the user a means to adjust the backlight intensity dynamically based upon the content of the display. Four integrated LDOs are fully configurable through I2C capable of addressing point-of-load regulation needs for functions such as integrated camera modules. The LDOs can be powered from main battery source, or by a fixed output voltage of an external buck converter (post regulation) leading to higher conversion efficiency. The LM3537 provides excellent efficiency without the use of an inductor by operating the charge pump in a gain of 3/2 or in Pass Mode. The proper gain for maintaining current regulation is chosen, based on LED forward voltage, so that efficiency is maximized over the input voltage range. LM3537 is offered in a tiny 30-bump DSBGA package. The LM3537 is a highly integrated LED driver capable of driving 8 LEDs in parallel for single display backlighting applications. Independent LED control allows for a subset of the main display LEDs to be selected for partial illumination applications. I2C-compatible control allows full configurability of the backlighting function. The LM3537 provides multi-zone Ambient Light Sensing allowing autonomous backlight intensity control in the event of changing ambient light conditions. A PWM input is also provided to give the user a means to adjust the backlight intensity dynamically based upon the content of the display. Four integrated LDOs are fully configurable through I2C capable of addressing point-of-load regulation needs for functions such as integrated camera modules. The LDOs can be powered from main battery source, or by a fixed output voltage of an external buck converter (post regulation) leading to higher conversion efficiency. The LM3537 provides excellent efficiency without the use of an inductor by operating the charge pump in a gain of 3/2 or in Pass Mode. The proper gain for maintaining current regulation is chosen, based on LED forward voltage, so that efficiency is maximized over the input voltage range. LM3537 is offered in a tiny 30-bump DSBGA package.

The LM3538 is a highly integrated LED driver capable of driving 6 LEDs in parallel for single display backlighting applications. Independent LED control allows for a subset of the main display LEDs to be selected for partial illumination applications. I2C-compatible control allows full configurability of the backlighting function. The LM3538 provides multi-zone Ambient Light Sensing allowing autonomous backlight intensity control in the event of changing ambient light conditions. A PWM input is also provided to give the user a means to adjust the backlight intensity dynamically based upon the content of the display. Four integrated LDOs are fully configurable through I2C capable of addressing point-of-load regulation needs for functions such as integrated camera modules. The LDOs can be powered from main battery source, or by a fixed output voltage of an external buck converter (post regulation) leading to higher conversion efficiency. The LM3538 provides excellent efficiency without the use of an inductor by operating the charge pump in a gain of 3/2 or in Pass-Mode. The proper gain for maintaining current regulation is chosen, based on LED forward voltage, so that efficiency is maximized over the input voltage range LM3538 is offered in a tiny 30-bump DSBGA package. The LM3538 is a highly integrated LED driver capable of driving 6 LEDs in parallel for single display backlighting applications. Independent LED control allows for a subset of the main display LEDs to be selected for partial illumination applications. I2C-compatible control allows full configurability of the backlighting function. The LM3538 provides multi-zone Ambient Light Sensing allowing autonomous backlight intensity control in the event of changing ambient light conditions. A PWM input is also provided to give the user a means to adjust the backlight intensity dynamically based upon the content of the display. Four integrated LDOs are fully configurable through I2C capable of addressing point-of-load regulation needs for functions such as integrated camera modules. The LDOs can be powered from main battery source, or by a fixed output voltage of an external buck converter (post regulation) leading to higher conversion efficiency. The LM3538 provides excellent efficiency without the use of an inductor by operating the charge pump in a gain of 3/2 or in Pass-Mode. The proper gain for maintaining current regulation is chosen, based on LED forward voltage, so that efficiency is maximized over the input voltage range LM3538 is offered in a tiny 30-bump DSBGA package.

The LM3549 is a high power LED driver with up to 700mA output current. It has three constant current LED drivers and a buck boost SMPS for driving RGB LEDs with high efficiency. LED drivers are designed for sequential drive so only one driver can be enabled at a time. LED driver output current settings can be stored to integrated non-volatile memory which allows stand-alone operation without I2C interface. Non-volatile memory is rewritable so current setting can be changed if needed. The LM3549 has a fault detection feature that can detect several different fault conditions. In case of a fault error flags are set and FAULT output sends interrupt to control logic. Error flags can be read through I2C interface. Total brightness can be controlled with PWM input or with master fader register if I2C interface is used. The LM3549 is a high power LED driver with up to 700mA output current. It has three constant current LED drivers and a buck boost SMPS for driving RGB LEDs with high efficiency. LED drivers are designed for sequential drive so only one driver can be enabled at a time. LED driver output current settings can be stored to integrated non-volatile memory which allows stand-alone operation without I2C interface. Non-volatile memory is rewritable so current setting can be changed if needed. The LM3549 has a fault detection feature that can detect several different fault conditions. In case of a fault error flags are set and FAULT output sends interrupt to control logic. Error flags can be read through I2C interface. Total brightness can be controlled with PWM input or with master fader register if I2C interface is used.

The LM3550 device is a low-noise, switched-capacitor DC-DC converter designed to operate as a current-limited and adjustable (up to 5.3 V) super-capacitor charger. The LM3550 features user-selectable termination voltages and provides one adjustable constant current output (up to 200 mA) and one NFET controller ideal for driving one or more high-current LEDs in a high-power flash mode or a low-power torch mode. The LED current and flash pulse duration of the LM3550 can be programmed via an I2C-compatible interface. The STROBE pin allows the flash to be toggled via a flash-enable signal from a controller or camera module. TheEOCpin sinks current when the output voltage reaches 95% of the final value. The ALD/TEMP input pin allows either a light sensor to adjust the flash-current level based on the ambient light conditions, or it allows for over-temperature detection and protection of the LED during high-power operation or high ambient-temperature conditions. The LM3550 device is a low-noise, switched-capacitor DC-DC converter designed to operate as a current-limited and adjustable (up to 5.3 V) super-capacitor charger. The LM3550 features user-selectable termination voltages and provides one adjustable constant current output (up to 200 mA) and one NFET controller ideal for driving one or more high-current LEDs in a high-power flash mode or a low-power torch mode. The LED current and flash pulse duration of the LM3550 can be programmed via an I2C-compatible interface. The STROBE pin allows the flash to be toggled via a flash-enable signal from a controller or camera module. TheEOCpin sinks current when the output voltage reaches 95% of the final value. The ALD/TEMP input pin allows either a light sensor to adjust the flash-current level based on the ambient light conditions, or it allows for over-temperature detection and protection of the LED during high-power operation or high ambient-temperature conditions.

The LM3553 is a fixed frequency, current mode step-up DC/DC converter with two regulated current sinks. The device is capable of driving loads up to 1.2A from a single-cell Li-Ion battery. The LM3553 includes a TX pin that forces Torch mode during a flash event allowing for synchronization between the RF power amplifier and Flash/Torch modes. It also includes a multi-function pin (M/F) that can serve as a GPIO and a hardware RESET pin. The LM3553 is available in a 3mm by 3mm package. The LM3553 is a fixed frequency, current mode step-up DC/DC converter with two regulated current sinks. The device is capable of driving loads up to 1.2A from a single-cell Li-Ion battery. The LM3553 includes a TX pin that forces Torch mode during a flash event allowing for synchronization between the RF power amplifier and Flash/Torch modes. It also includes a multi-function pin (M/F) that can serve as a GPIO and a hardware RESET pin. The LM3553 is available in a 3mm by 3mm package.

The LM3554 is a 2-MHz fixed-frequency, current-mode synchronous boost converter. The device is designed to operate as a dual 600-mA (1.2 A total) constant-current driver for high-current white LEDs, or as a regulated 4.5-V or 5-V voltage source. The main features include: an I2C-compatible interface for controlling the LED current or the desired output voltage, a hardware flash enable input for direct triggering of the flash pulse, and dual TX inputs which force the flash pulse into a low-current torch mode allowing for synchronization to RF power amplifier events or other high-current conditions. Additionally, an active high hardware enable (HWEN) input provides a hardware shutdown during system software failures. Five protection features are available within the LM3554 including a software selectable input voltage monitor, an internal comparator for interfacing with an external temperature sensor, four selectable current limits to ensure the battery current is kept below a predetermined peak level, an overvoltage protection feature to limit the output voltage during LED open circuits, and an output short circuit protection which limits the output current during shorts to GND. The LM3554 is a 2-MHz fixed-frequency, current-mode synchronous boost converter. The device is designed to operate as a dual 600-mA (1.2 A total) constant-current driver for high-current white LEDs, or as a regulated 4.5-V or 5-V voltage source. The main features include: an I2C-compatible interface for controlling the LED current or the desired output voltage, a hardware flash enable input for direct triggering of the flash pulse, and dual TX inputs which force the flash pulse into a low-current torch mode allowing for synchronization to RF power amplifier events or other high-current conditions. Additionally, an active high hardware enable (HWEN) input provides a hardware shutdown during system software failures. Five protection features are available within the LM3554 including a software selectable input voltage monitor, an internal comparator for interfacing with an external temperature sensor, four selectable current limits to ensure the battery current is kept below a predetermined peak level, an overvoltage protection feature to limit the output voltage during LED open circuits, and an output short circuit protection which limits the output current during shorts to GND.