Hi, I'm considering using the HMC981 for controlling bias on the HMC996 VGA. I have a few questions:
1) Is this part compatible with the HMC996?
2) If the HMC981 controls two gate voltages, how come there is only one drain voltage input for current…
I'm designing the HMC996 into my receiver and would like to know if there is recommended circuitry for driving the gain control Vctrl pin, and be able to vary it digitally ?
Many thanks in advance.
Thanks for your advice.
I want to use the 5721R to control the gain of the HMC996 VGA.
It requires a -4.5 to 0V voltage.
I am also using a HMC980LP4E to generate the 2 gate voltages that control
the bias current.
Thank you for your answer.
I have additional question. Does HMC996 has damaged by the following sequence?
1. Vgg(-2V) → Vctrl → Vdd → Vgg（Idq 120mA）
2. Vgg(-2V) → Vdd → Vctrl → Vgg（Idq 120mA）
3. Vgg(-2V) → Vdd → Vgg（Idq 120mA） → Vctrl