Microchip Adds Positively-Regulated Charge Pumps
Microchip Technology Inc. has added a new family of positively regulated charge pump dc-dc converters that the company claims are among the most highly efficient charge pumps in the industry. The first fractional charge pumps in Microchip's portfolio, the MCP1256, MCP1257, MCP1258 and MCP1259 devices automatically switch between 1.5x and 2x boost operation for improved efficiency. They are designed for use in dual-cell alkaline, Ni-Cd, Ni-MH, single-cell Mn02 and similar coin-cell battery systems.
These new devices provide a low-cost alternative in the high efficiency, low-power and low- noise charge pump category. At light output loads, the MCP1256 and MCP1257 can be placed in "Sleep" mode, where quiescent current is lowered but regulated output voltage stays the same. Additionally, the MCP1258 and MCP1259 devices provide a bypass feature that connects the input voltage to the output, which biases the system's real-time clock and microprocessor/microcontroller with virtually no power drain from the charge pump itself. All of the MCP125X devices have a low-noise output ripple of less than 20mVpp at load currents up to 100mA, resulting in less system interference and better overall performance.
"Designers of battery-powered consumer electronics are challenged to create highly efficient products with low power dissipation and long battery life," said Qi Deng, senior product marketing engineer with Microchip's Analog and Interface Products Division. "The MCP1256 – MCP1259 charge pumps address these challenges, plus they provide other features important to our customers, such as soft start, short-circuit protection and thermal protection. Their extended temperature operation (-40 to +125 degrees Celsius) and small, thermally capable DFN packaging make them extremely versatile for the wide variety of environments with which our customers work."
The MCP125X charge pump dc-dc converters are ideal for battery-powered consumer electronics devices that require low power and utilize white light-emitting-diode (LED) backlights for liquid-crystal displays (LCDs). Example devices include digital cameras, MP3 players, personal media players and digital multimedia broadcasting players. The devices are also appropriate for noise-sensitive industrial applications that involve white LED backlights for LCDs, such as thermostat controllers, machine control panels, handheld meters and scanners, and communications devices such as handheld global-positioning-system and two-way radio devices.
Pricing for the MCP1256, MCP1257, MCP1258 and MCP1259 charge pump converters is $1.49 each in 10,000-unit quantities for all devices and package options. The devices are available in 10-pin MSOP or thermally capable DFN (3 mm x 3 mm) packages.
