Where can I find examples that implements ECDSA and ECDH using light weight version of bouncycastle and uses bouncy castle provider dynamically?
The bouncycastle java crypto library has two basic modes. It can be use as a JCE provider, and as a standalone library accessed through its lightweight API. You can even use both at the same time if you prefer, EXCEPT in J2ME (now known as JME). You can only use the lightweight API in J2ME. You can find the J2ME version of the bouncycastle library on their latest releases page.