What is a step-down transformer? Md. Saifur Rahman The transformer which converts a low flow of current with a high flow of current with low voltage is called a step-down transformer.You may likeDo I need car insurance?What is car insurance?How could I get cheaper car insurance?What is auto insurance?Why Adulterant food is the barrier to sound health?What are the producers?What are food preservatives?What is food chain?What is tertiary consumer?