Telefonaktiebolaget Lm Ericsson (publ)

Christian Bjork

Bojko Marholev

Torbjorn Gardenfors

Martin Lantz

Sven Erik Mattisson

A power-on reset circuit with glitch sensing capabilities is formed as part of the same integrated circuit chip containing other logical circuits. A port included in the integrated circuit chip enables a power-on reset signal generated by the integrated power-on reset circuit to be output from the chip and applied to other chips installed in a single chip or multi-chip electronic system. The power-on reset circuit compares a capacitor stored reset voltage to a reference voltage and outputs the power-on reset signal when the reset voltage falls below the reference voltage. Storage of the reset voltage by the capacitor is controlled by a glitch sensor which detects changes in voltage provided by a power supply in excess of a given threshold and, in response thereto, triggers a capacitor discharge. This causes the reset voltage to fall below the reference voltage, and the power-on reset signal to be output. Furthermore, for synchronously operated systems, the output power-on reset signal is synchronized with an edge of an output clock signal.

Electronic system having a chip integrated power-on reset circuit with

An antenna switch for selectively connecting an output differential signal pair of an output power amplifier to a single-ended signal of an antenna when transmitting and selectively connecting an input differential signal pair of a low noise input amplifier to the single-ended signal of the antenna when receiving. A first balun having a single ended-signal connected to an antenna connects a first and second output differential signal to a power output amplifier. A second balun having a single-ended signal connected to the antenna connects a first and second input differential signal to a low noise input amplifier. A first diode selectively shorts the first output differential signal to the second output differential signal of the first balun when receiving and a second diode selectively shorts the first input differential signal to the second input differential signal of the second balun when transmitting.

Monolithic high frequency antenna switch

A monolithic high frequency voltage controlled oscillator trimming circuit includes a plurality of capacitance loops selectively connected between a first and second differential input of a voltage oscillator active network. A plurality of diodes, connected in series with the respective plurality of capacitance loops, selectively connect respective capacitance loops between the first and second differential input when forward biased. In a similar fashion, the plurality of diodes selectively disconnect the respective capacitance loops from the first and second differential input when reverse biased. A controller applies a forward biasing voltage to the diode of the selected capacitance loop to connect the capacitance loop to the active network of the voltage controlled oscillator and applies a reverse biasing voltage to the diode of the selected capacitance loop to disconnect the capacitance loop from the active network. The diodes used in the capacitance loops form a switch operable at high frequencies and are formed from a bipolar complementary metal oxide semiconductor electro-static discharge protection diode.

Growing community of inventors

.ANG.Karp, Sweden

Christian Bjork