March 8, 2012 – Linear Technology Korea (CEO Hong Sa-kwak) announced the development of a pushbutton on/off controller (product name: LTC2955) capable of managing system power from 1.5V to 36V via a pushbutton interface or power supply. Unlike typical pushbutton controllers that initiate system power-up solely through a pushbutton toggle, the LTC2955 automatically starts the system when power is supplied through a primary or secondary power source, such as an electrical outlet or a car battery. Upon power-up, the LTC2955 can power down the system via a pushbutton, and optionally, interrupt logic can be used to request a system power-down from a menu-driven application ('soft' shutdown). Alternatively, it can automatically power down the system when no power is available. Another key feature is that absolutely no code is required for the device's configuration. The LTC2955 is a simple yet configurable high-voltage pushbutton controller that provides a set of generally common on/off power options.
The LTC2955 features a wide operating range of 1.5V to 36V, making it suitable for a diverse range of single-cell, multi-cell, and high-voltage applications, including desktop and laptop computers, consumer electronics, portable devices, and automotive electronics. The powerful pushbutton input can handle a wide voltage swing of up to ±36V and ESD strikes up to ±25kV, and is designed to operate even in noisy environments. Automatic turn-on/turn-off combinations can be selected using the mode selection pin, and battery runtime is maximized thanks to a low standby current of 1.2µA. The LTC2955 is characterized by its PowerGood output, interrupt output, and kill input, which provide a simple interface along with microprocessor options. If the microprocessor fails to respond to an interrupt request, the user can use an adjustable turn-off timer to set the time during which the push button must be suppressed for forced system power-down.
The LTC2955 is available with both positive (LTC2955-1) and negative (LTC2955-2) enabled polarities and is supplied in 10-pin 3mm x 2mm DFN or 8-pin ThinSOT™ packages. Available in commercial and industrial temperature ranges, the LTC2955 is priced starting at $1.98 per unit for 1,000-unit volumes. For more information, visit www.linear.com/pushbutton .

Photo caption: Push-button on/off control with automatic turn-on function upon power supply

Product Features: LTC2955

• Automatic turn-on function for voltage monitor input
• Wide input supply voltage range: 1.5V ~ 36V
• Low supply current: 1.2µA
• ±25kV ESD HBM at PB input
• Wide input voltage of ±36V for /PB input
• DC/DC converter control possible with low leakage EN output (LTC2955-1)
• External P-channel MOSFET can be driven with high voltage/EN output (LTC2955-2)
• Smooth µP shutdown possible with a simple interface
• Adjustable turn-off timer
• 10-pin 3mm x 2mm DFN and 8-pin ThinSOT™ packages