LTC5533 UUWUAPPLICATIO S I FOR ATIO 3600 V Figure 2 shows the corresponding slope of the 11GHz CC = 3.6V 3200 VOS = 0V response, and Figure 3 shows the variation of the output 2800 voltage vs RF input power at –40°C and 85°C, normalized 2400 to the room temperature (25°C) results. 2000 The LTC5533 can be used as a demodulator for AM and 1600 TA = –40°C ASK modulated signals with data rates up to 2MHz. 1200 OUTPUT VOLTAGE (mV) T Depending on specific application needs, the detector A = 25°C OUT 800 V outputs can be split between two branches, providing AC- 400 T coupled data (or audio) output and a DC-coupled RSSI A = 85°C 0 –32 –28 –24 –20 –16 output for signal strength measurements and AGC. –12 –8 –4 0 4 8 12 RF INPUT POWER (dBm) The LTC5533 can also be used for RF power detection and 5533 F01 control. Figure 4 is an example of an LTC5533 used for Figure 1. Typical Detector Characteristics, 11GHz dual band mobile phone transmitter power control. The LTC5533 consists of two separate RF detector dice 1000 VCC = 3.6V packaged together. Consequently, detector-to-detector VOS = 0V isolation is good—typically 45dB at 2GHz. Output match- ing is good, but not precise. The characterization plots in 100 the Typical Performance Characteristics show that the typical output voltage mismatch is within ±25mV with no SLOPE (mV/dB) TA = –40°C TA = 85°C RF input signal present. With –14dBm RF input signal, the OUT 10 V typical equivalent mismatch is within ±1dB. TA = 25°C 1 –32 –28 –24 –20 –16 –12 –8 –4 0 4 8 RF INPUT POWER (dBm) C3 + 20dB RESISTIVE TAP ANTENNA 5533 F02 0.1µF Li-Ion C1 Figure 2. VOUT Slope vs RF Input Power at 11GHz LTC5533 39pF R1 360 1 12 Ω VCC1 RFIN1 2 11 V GND 3 OUT1 V 3 10 14dB RESISTIVE TAP CC = 3.6V V SHDN1 V OS1 OS = 0V 4 9 2 VCC2 RFIN2 5 8 R2 V GND C2 T OUT2 150Ω 1 A = –40°C 6 7 39pF VOS2 SHDN2 0 CELL BAND DIPLEXER VARIATION (dB) –1 OUTV TA = 85°C PCS BAND –2 –3 –24 –20 –16 –12 –8 –4 0 4 8 12 MOBILE PHONE BB/DSP VPC 5533 F04 RF INPUT POWER (dBm) BSE 5533 F03 Tx PA MODULE Figure 3. VOUT Variation at –40 ° C and at 85 ° C vs RF Input Powerat 11GHz, Normalized to Room Temperature (25 ° C) Results.Figure 4. Dual Band Mobile Phone Transmitter Power Contol with LTC5533 5533f 10