LMV225 linear radio frequency power meter

US National Semiconductor LMV225 is a linear radio frequency power meter integrated circuit for SMD packaging. It can be used in the frequency range of 450 MHz to 2000 MHz, only four external components. Enter the DC voltage of the input signal from the coupling capacitor. 10K resistor loads the DC voltage in the input pin, enables or disables integrated circuits depending on the voltage level. If it is above 1.8V, the detector is enabled, the current consumes 5-8 mA. If the pin A1 voltage is less than 0.8V, IC enters the shutdown mode, only a few micro-security is consumed. The power supply voltage can be between 2.7V and 5.5V, and a 100NF capacitor is filtered from the remaining RF signal. Finally, there is a low-pass filter formed by an output capacitor to combine the internal circuit of the LMV225. If the capacitance value is 1NF, the corner frequency of the low pass filter is about 8 kiloz. Output, has a relatively high impedance, provides an output voltage, proportional to the signal power, and the slope of 40 millivolts / decibels. The output is 2 V at 40 dBm 9 dBm -0.4 V. Level 0 DBM corresponds to a 1 MW, 50 river a sinusoidal waveform, which is equal to the effective voltage of 224 millivolts. The relationship between modulation signals, power, and voltage is usually different. This table shows an example of the power and voltage of several sinusoidal signals. The input impedance of the LMV225 detector is approximately 50 r characteristic impedances for radio frequency circuits that provide a good match. The 40 decibration measurement range for the LMV225 table can be transferred to a higher power level and use a series of input resistors. The LMV225 was originally designed to be in a mobile phone, so it was encapsulated in a solder bump size of only 1 × 1 mm and four (similar to the ball grid array package). The connection is labeled as A1, A2, B1, B1, elements like a matrix. Tap in the A1 angle.

Leave a message 

Message List