HMC7229LS6 Datasheet, PDF (13/16 Pages) Hittite Microwave Corporation – GaAs pHEMT MMIC 1 WATT POWER AMPLIFIER With Power Detector, 37 - 40 GHz

HMC7229LS6
APPLICATIONS INFORMATION
Figure 35 shows the basic connections for operating the
HMC7229LS6 and see the Theory of Operation section for
additional details. The RF input and RF output are ac-coupled
by the internal dc block capacitors. To avoid damaging the
HMC7229LS6, follow the recommended bias sequencing
during power-up and power-down.
The gate bias of the HMC7229LS6 is supplied by using either
the VGG1 pin or the VGG2 pin. While applying drain bias to the
HMC7229LS6, all of the VDD1, VDD2, VDD3, and VDD4 pins must
be used.
RECOMMENDED BIAS SEQUENCE
During Power-Up
The recommended bias sequence during power-up is the
following:
1. Connect the GND pin to ground.
2. Set VGGx to −2 V.
3. Set VDDx to 6 V.
4. Increase VGGx to achieve a typical IDD = 1200 mA.
5. Apply the RF signal.
Data Sheet
During Power-Down
The recommended bias sequence during power-down is the
following:
1. Turn the RF signal off.
2. Decrease VGGx to −2 V to achieve a typical IDD = 0 mA.
3. Decrease VDDx to 0 V.
4. Increase VGGx to 0 V.
The bias conditions previously listed (VDDx = 6 V, IDD = 1200 mA),
are the recommended operating point to get optimum
performance. The data used in this data sheet was taken with
the recommended bias condition. When using the HMC7229LS6
with different bias conditions, different performance may result
than what is shown in the Typical Performance Characteristics
section.
The VDET and VREF pins are the output pins for the internal
power detector. The VDET pin is the dc voltage output pin that
represents the RF output power rectified by the internal diode,
which is biased through an external resistor.
The VREF pin is the dc voltage output pin that represents the
reference diode voltage, which is biased through an external
resistor. This voltage then compensates for the temperature
variation effects on both diodes. A typical circuit is shown in
the Typical Application Circuit section that reads out the output
voltage and represents the RF output power shown in Figure 35.
Rev. B | Page 12 of 15