恒压二极管

• 厂(rock face; eaves)RADICAL
• 土(earth; soil; ground)ASSOCIATIVE
• 丶(small dot; weight)ASSOCIATIVE

A rock wall pressing down on the earth like a heavy object applying pressure from above.

• 二(number two; two horizontal strokes)ASSOCIATIVE

Two parallel horizontal strokes symbolize the number two.

• 木(tree; wood)RADICAL
• 及(reach; attain; catch up)PHONO-SEMANTIC

An extreme point is the uttermost end of a wooden pole, where a hand just barely reaches.

• ⺮(bamboo)RADICAL
• 官(official; manage)PHONO-SEMANTIC

A bamboo tube is managed by officials, so 管 means both tube and to manage.