Integrated circuit package for isolation dies

1. An isolation device comprising:

an isolation die having bond pads;

a first lead frame having first leads, the isolation die being mounted on the first lead frame with a portion of the bond pads coupled to respective first leads;

first mold material encapsulating the isolation die and the first lead frame forming a first package;

a second lead frame having second leads, the first package being mounted on the second lead frame with a portion of the first leads coupled to respective second leads; and

second mold material encapsulating the first package and the second lead frame, wherein the second lead frame is a pre-molded lead frame, further comprising a third mold material encapsulating the second lead frame and forming a flat surface on which the first package is mounted.

2. An isolation device comprising:

an isolation die having bond pads;

a first lead frame having first leads, the isolation die being mounted on the first lead frame with a portion of the bond pads coupled to respective first leads, wherein the first lead frame is plated with a first material;

first mold material encapsulating the isolation die and the first lead frame forming a first package;

a second lead frame having second leads, the first package being mounted on the second lead frame with a portion of the first leads coupled to respective second leads, wherein the second lead frame is plated with a second material that is different from the first material; and

second mold material encapsulating the first package and the second lead frame.

3. A system comprising:

a substrate that includes a first voltage domain and a second voltage domain;

first circuitry mounted on the substrate in the first voltage domain, the first circuitry having a first signal terminal;

second circuitry mounted on the substrate in the second voltage domain, the second circuitry having a second signal terminal; and

an isolation device having an input terminal coupled to the first terminal and an output terminal coupled to the second terminal, wherein the isolation device comprises:

an isolation die having bond pads;

a first lead frame having first leads, the isolation die being mounted on the first lead frame with a portion of the bond pads coupled to respective first leads;

first mold material encapsulating the isolation die and the first lead frame forming a first package;

a second lead frame having second leads, the first package being mounted on the second lead frame with a portion of the first leads coupled to respective second leads; and

second mold material encapsulating the first package and the second lead frame, wherein the second lead frame is a pre-molded lead frame, further comprising a third mold material encapsulating the second lead frame and forming a flat surface on which the first package is mounted.

4. A system comprising:

a substrate that includes a first voltage domain and a second voltage domain;

first circuitry mounted on the substrate in the first voltage domain, the first circuitry having a first signal terminal;

second circuitry mounted on the substrate in the second voltage domain, the second circuitry having a second signal terminal; and

an isolation device having an input terminal coupled to the first terminal and an output terminal coupled to the second terminal, wherein the isolation device comprises:

an isolation die having bond pads;

a first lead frame having first leads, the isolation die being mounted on the first lead frame with a portion of the bond pads coupled to respective first leads, wherein the first lead frame is plated with a first material;

first mold material encapsulating the isolation die and the first lead frame forming a first package;

a second lead frame having second leads, the first package being mounted on the second lead frame with a portion of the first leads coupled to respective second leads, wherein the second lead frame is plated with a second material that is different from the first material; and

second mold material encapsulating the first package and the second lead frame.

5. A method for fabricating an isolation device, the method comprising:

fabricating an isolation die having bond pads;

mounting the isolation die on a first lead frame having first leads;

coupling a portion of the bond pads to respective first leads;

encapsulating the isolation die and the first lead frame with a first mold material to form a first package;

pre-molding a second lead frame having second leads with a second mold material to form a flat surface on which the first package is to be mounted;

mounting the first package on a second lead frame;

coupling a portion of the first leads to respective ones of the second leads; and

encapsulating the first package and the second lead frame with a second mold material.

6. A method for fabricating an isolation device, the method comprising:

fabricating an isolation die having bond pads;

mounting the isolation die on a first lead frame having first leads;

coupling a portion of the bond pads to respective first leads;

encapsulating the isolation die and the first lead frame with a first mold material to form a first package;

mounting the first package on a second lead frame having second leads;

coupling a portion of the first leads to respective second leads; and

encapsulating the first package and the second lead frame with a second mold material, further comprising plating the first lead frame with a first material and plating the second lead frame with a second material that is different from the first material.