Apparatuses for signal boost are disclosed. An example apparatus includes: first and second digit lines coupled to memory cells; a sense amplifier including: first and second transistors having gates operatively coupled to the first digit line and drains coupled to a first node, sources of the first and second transistors coupled to first and second control lines providing first and second power supply voltage respectively; and third and fourth transistors having gates coupled to the second digit line and drains coupled to a second node, sources of the third and fourth transistors coupled to the first and second control lines respectively; a power line coupled to the first node and the second node; and a power switch providing either the first power supply voltage or a third power supply voltage smaller than the first power supply voltage to the power line.