Handheld electronic device
A mobile phone may include an enclosure defining an internal volume, the enclosure including a front cover formed from a transparent material and defining a front exterior surface, a rear cover formed from a glass material and defining a rear exterior surface, and a housing component defining a side exterior surface. The mobile phone may include a circuit board assembly within the internal volume. The circuit board assembly may include a circuit board, a circuit component coupled to an exterior surface of the circuit board, and a cowling coupled to the circuit board and covering the circuit component, the cowling having a thickness less than about 0.5 mm and including a base structure formed from an aluminum alloy having a thickness less than about 0.4 mm and a thermally conductive structure positioned over the base structure and configured to dissipate heat.
1. A mobile phone comprising:
an enclosure defining an internal structure, the enclosure comprising:
a front cover assembly comprising a front cover formed from a transparent material and defining a front exterior surface of the mobile phone;
a rear cover formed from a glass material and defining a rear exterior surface of the mobile phone; and
a housing component defining a side exterior surface of the mobile phone; and
a circuit board assembly positioned on the internal structure and comprising:
a circuit board;
a circuit component coupled to an exterior surface of the circuit board;
a cowling coupled to a first side of the circuit board assembly and covering the circuit component, the cowling having a thickness less than about 0.5 mm and comprising:
a base structure formed from an aluminum alloy having a thickness less than about 0.4 mm;
a first thermally conductive structure positioned over the base structure and configured to dissipate heat from the circuit board assembly; and
a second thermally conductive structure positioned on the second side of the circuit board assembly;
a first thermal bridge coupled to the first thermally conductive structure and thermally coupling the circuit board assembly to the front cover assembly; and
a second thermal bridge coupled to the second thermally conductive structure and thermally coupling the circuit board assembly to the internal structure of the enclosure.
2. The mobile phone of claim 1 , wherein the aluminum alloy is a 7475 series aluminum alloy.
3. The mobile phone of claim 1 , wherein the thermally conductive structure comprises graphite.
4. The mobile phone of claim 1 , wherein the thermally conductive structure comprises a multi-layer structure including:
a plurality of graphite layers; and
a plurality of adhesive layers.
5. The mobile phone of claim 1 , wherein:
the cowling defines a bend segment extending from a main portion of the cowling to a raised portion of the cowling; and
the bend segment has bend radius that is greater than about 0.5 mm.
6. The mobile phone of claim 5 , wherein a thickness of the cowling in the raised portion is less than a thickness of the cowling in the main portion.
7. A portable electronic device comprising:
an enclosure comprising:
a housing structure comprising:
a first wall section defining a first side exterior surface of the portable electronic device;
a second wall section defining a second side exterior surface opposite to the first side exterior surface; and
a mid-chassis section extending between the first wall section and the second wall section;
a front cover assembly coupled to the housing structure and comprising a first transparent member defining a front surface of the portable electronic device; and
a rear cover assembly coupled to the housing structure and comprising a second transparent member defining a rear surface of the portable electronic device;
a display at least partially within the enclosure and below the front cover assembly;
a battery at least partially within the enclosure;
a circuit board assembly at least partially within the enclosure and comprising:
a circuit board; and
a cowling coupled to the circuit board and defining an exterior surface of the circuit board assembly, the cowling comprising:
an aluminum alloy base structure; and
a graphite layer over the aluminum alloy base structure; and
a first thermal bridge coupled to the circuit board assembly and thermally coupling the circuit board assembly to the front cover assembly; and
a second thermal bridge coupled to the circuit board assembly structure and thermally coupling the circuit board assembly to the mid-chassis section of the enclosure.
8. The portable electronic device of claim 7 , wherein the cowling covers substantially an entire top surface of the circuit board.
9. The portable electronic device of claim 8 , wherein:
the circuit board assembly comprises:
a first circuit component coupled to the top surface of the circuit board; and
a second circuit component coupled to the top surface of the circuit board; and
the cowling covers the first circuit component and the second circuit component.
10. The portable electronic device of claim 7 , wherein the aluminum alloy base structure is formed of a 7475 series aluminum alloy.
11. The portable electronic device of claim 10 , wherein the aluminum alloy base structure has a thickness less than about 0.4 mm.
12. The portable electronic device of claim 7 , wherein:
the graphite layer is a first graphite layer;
the cowling is coupled to a first side of the circuit board assembly; and
the circuit board assembly further comprises a multi-layer thermally conductive structure coupled to a second side of the circuit board assembly and comprising:
a plurality of second graphite layers; and
a plurality of adhesive layers.
13. The portable electronic device of claim 7 , wherein:
the circuit board is a first circuit board; and
the circuit board assembly further comprises:
a wall structure coupled to the first circuit board; and
a second circuit board coupled to the wall structure and supported above the first circuit board by the wall structure.
14. An electronic device comprising:
a display;
a battery; and
an enclosure enclosing the display and the battery, the enclosure comprising:
a front cover assembly defining a front exterior surface of the electronic device;
a rear cover assembly defining a rear exterior surface of the electronic device; and
a housing component comprising:
a first wall section defining a first side exterior surface of the electronic device;
a second wall section defining a second side exterior surface opposite to the first side exterior surface; and
a mid-chassis section extending between the first wall section and the second wall section;
a circuit board assembly coupled to the mid-chassis section and defining a first peripheral side proximate the first wall section of the housing component and a second peripheral side opposite the first peripheral side; and
a thermal bridge thermally coupling the circuit board assembly to the mid-chassis section, the thermal bridge positioned proximate the first peripheral side of the circuit board assembly.
15. The electronic device of claim 14 , wherein a center of the thermal bridge is offset from a midline of the circuit board assembly.
16. The electronic device of claim 14 , wherein:
the thermal bridge is a first thermal bridge; and
the electronic device further comprises a second thermal bridge thermally coupling the circuit board assembly to the front cover assembly.
17. The electronic device of claim 14 , wherein:
the thermal bridge is a first thermal bridge;
the circuit board assembly defines:
a first segment extending along a first side of the battery; and
a second segment extending along a second side of the battery, the second side perpendicular to the first side;
the first thermal bridge is positioned on the first segment of the circuit board assembly; and
the electronic device further comprises a second thermal bridge positioned on the second segment of the circuit board assembly.
18. The electronic device of claim 17 , wherein:
the circuit board assembly further comprises:
a first cowling coupled to the first segment of the circuit board assembly and covering a first circuit component of the circuit board assembly;
a second cowling coupled to the second segment of the circuit board assembly and covering a second circuit component of the circuit board assembly; and
a thermally conductive structure extending over both the first cowling and the second cowling; and
the first thermal bridge and the second thermal bridge are coupled to the thermally conductive structure.