Chandragomin (Skt. Candragomin) was a renowned 7th century CE Indian Buddhist lay master and scholar who dressed in the white robes of the Yogic tradition and mastered the morality of the five precepts. He was born into a Kshatriya family in the northern Varendra region which is now a part of Bangladesh.
According to Thrangu Rinpoche, Chandragomin was slow in the debate but always had the right answers because each time a question was posed by Chandrakirti, Chandragomin would insist on giving the answer the next day after praying to Avalokiteshvara who would tell him the right answer. 
Translated from the original Buddhist Hybrid Sanskrit into Tibetan is Chandragomin's 'Shurangama MantraSadhana' (Tibetan canonTengyurKarchag Phangthangma Toh 3096, Toh 593/2/1). It is titled Sarvatathāgataoṣṇīṣaśitātapatrā-nāmāparājitā-mahāpratyangirā-mahāvidyārājñī-nāma-dhāraṇī; Tibetan name is ['phags pa] De bshin gshegs pa'i gtsug tor nas byung ba'i gdugs dkar po can gshan gyi mi thub pa phir bzlog pa chen mo mchog tu grub pa shes bya ba'i gzungs.
Peerless king of physicians, guru of the world, Totally faultless one, source of virtuous qualities, Having visualised you, 0 refuge, I, always ill, Shall confess, describing my changes of fault. With whatever high mind is appropriate, Abiding in whatever calm state is appropriate, Who pacifies all the faults in all the modes, Whatever the Lord may be, that I salute.