TI high-efficiency charge pump with I2C interface drives seven white LEDs
-- Tiny, Flexible Converter Supports up to Five LEDs for Main Display and Two LEDs for Sub-Displays
DALLAS - Texas Instruments Incorporated (TI) (NYSE: TXN) introduced today a high-efficiency, constant-frequency charge pump DC/DC converter that uses dual-mode conversion to maximize efficiency over the input voltage range.
The tiny 3 mm x 3 mm device provides a fully programmable current with I2C interface for applications, such as cellular phones, PDAs and multi-display handheld devices.
TI's TPS60250 drives up to five white LEDs for a main display and up to two white LEDs for a sub-display with regulated constant current for uniform intensity. By utilizing adaptive charge pump modes and very low-dropout current regulators, the TPS60250 achieves high efficiency over the full one-cell lithium-battery input voltage range.
Four enable inputs, available through I2C, are used for simple on/off controls for the independent displays. To lower operating current when using one sub-display LED, the device provides
completely separate operation in sub-display LEDs.
* 3-V to 6-V input voltage range
* 1x and 1.5x charge pump
* Fully programmable current with I2C
o 64 dimming steps with 25 mA maximum (sub and main display banks)
o 4 dimming steps with 80 mA maximum (DM5 for auxiliary application)
* Two percent current matching for sub-LEDs at light load condition
(each 100 µA)
* 750-kHz charge pump frequency
* Continuous 230-mA maximum output current
* Auto-switching between 1x and 1.5x mode for maximum efficiency
* Built-in soft start and current limit
* Open lamp detection
* 16-pin, 3 mm x 3 mm QFN
Pricing and Availability
The TPS60250 is shipping in volume production today from TI and its
worldwide network of distributors and packaged in a 3 mm x 3 mm, 16-pin QFN packaging. Suggested resale price starts at $1.40 in 1,000-unit quantities.
Lighting and Display Solutions
TI provides the broadest portfolio of high-performance products for
today's LED design requirements, along with local support and
applications expertise to help designers get to market faster. TI's LED products include power management, such as AC/DC, power factor
correction, DC/DC and linear power conversion; RF transceivers; digital signal processors (DSPs); and ultra-low-power microcontrollers (MCUs). TI's products support applications ranging from ultra-small portable displays to the largest lighting and display panels in the industry.
Texas Instruments European Product Information Centre Freising, Germany Tel: 49 8161 80 33 11 Fax: 49 8161 80 20 45