(Below are details from the Kamakoti peetam website Kamakoti.org acharya parampara)
Sri Sivanandendra Chidghanendra Saraswati : He was a Karnataka Brahmin and the son of one Ujjvala Bhatta. His poorvasrama name was Iswara Vatu. His predilections were towards Sivaadvaita. He attained mukti at Vrjddhachala on Sukla Dasami in the month of Jyestha of the cyclic year Virodhikrit (172 AD).
The pic below is a carving from one of the pillars which I believe depicts the acharya .
A new pic of the adhishtanam which I re visited last Sunday
11. Sri Sivananda Chidghanendra Saraswati
127 - 172 A.D.
आचाय - 11 - िशवानिचनेसरती
The boy Ăąvara, son of Ujjvala bhaṭṭa of Karnataka,
known as Cidghana, who approached Sureśvara and
acquired the knowledge of bhāṣyas etc., having got
his (Sureśvara’s) responsibility and remaining in the
Păṭha there, this Cidghana spent forty-five years as
if Ąiva Himself had come there to grant liberation to
those who seek liberation.
Revered by the wise, Cighana having placed
Vātsyāyāna, the initiated who was hailed as
Hari arrived from Milky Ocean, and imparting
the precepts he had attained his form, the pure
consciousness on the tenth day of the bright
fortnight in the month of Jyeṣṭha in the year
Virodhikṛt of the Kali era.