Our website uses cookies. By continuing to use this website, you consent to cookies being used. Find out how we manage cookies.

PGA-103+ Stablilizing Network

The PGA-103+ is a monolithic amplifier for the 50-4000 MHz range with excellent Noise Figure and a high dynamic range (1dB compression point: 22.5 dBm and ultra-high OIP3, 44 dBm typ. @ 2GHz). Due to the intrinsic nature of the GaAs PHEMT, it is not unconditionally stable (stability factor k>1 and stability measure B>0) as k

Figure 1 - PGA-103+: stability factor

In order to improve stability additional components need to be added at input, see Figure 2 and associated component values in Table 1.

Figure 2: Stabilization Circuit (Ref: TB-761-103+)
Table 2

The stability parameters of the amplifier with the stabilizing network are shown in Figure 3. Note: k>1 and B>0 over entire range.

The performance of the stabilized amplifier:

Performace with and without stabilization is shown in Figures 3 to 11

Figure 3 - Stability Factor (k-factor)
Figure 4 - Stability Measure
Figure 5 - Gain
Figure 6 - Isolation
Figure 7 - Input Return Loss
Figure 8 - Output Return Loss
Figure 9 - Output IP3
Figure 10 - Output power @ 1dB compression
Figure 11 Noise Figure


  • Use of the stabilization circuitry has minor impact on all parameters
  • The use of the stabilization circuitry guarantees amplifier's unconditional stability.