300 mA Low Noise LDO

Toshiba has announced a series of low noise low drop-out (LDO) voltage regulators in a 1 x 1 x 0.38mm plastic DFN4C package. Noise credentials are typically 5µVrms between 10Hz and 100kHz

There are 32 products in the TCR3RM series, as it will be known, with single fixed outputs spanning 0.9 to 4.5V.

Ripple rejection ratio is typically 100dB (1kHz, 2.8V output variant), and has a frequency characteristic optimised for post-regulating dc-dc converters.

“Unlike other LDO regulators where the ripple rejection ratio usually drops 20 dB every ten-fold increase in frequency, TCR3RM falls significantly less,” according to the company. “The rejection ratio at 1MHz [2.8V output] is 68dB.”

Noise and ripple performance, said Toshiba, is due to the design of internal bandgap circuit, low pass filter and a low-noise high-speed operational amplifier.

1μF input and output capacitors are required, which can be ceramic types.

Maximum output current of is 300mA and drop-out voltage is typically 130mV outputting 2.8V at 300mA.

Quiescent current is 12μA max across the operating range of -40 to 85°C.

A control pin turns the output on and off (high = on, low = off, open = off). An internal transistor automatically discharges output capacitance when the output is turned off. On stand-by, max current consumed across temperatre is 1μA (100nA typ 25°C)

Other features include over-current protection and thermal shutdown.

Applications are foreseen in portable and wearable devices, such as sensing, RF and IoT products.