RM590 Series: Synchronous Buck DC/DC Module with VFM/PWM Control and Built-in Inductor for Industrial and Consumer Applications

Ricoh Electronic Devices has launched the RM590 series with a synchronous buck DC/DC switching regulator and an inductor that is optimized for use in industrial and consumer applications. The RM590 series devices require only two external capacitors, which removes the necessity of complex wiring and enables designing a compact board with ease. This Series adopts a small QFN2220-8 package with a 2.2 x 2.0 x 1.5mm size and features a maximum output current of 400 mA. 

The RM590 series has two output voltage types: one is the fixed type, an internally fixed output voltage, and the other is the adjustable type, an output voltage variable with external resistors. This Series features an input voltage range from 2.3V to 5.5V with a maximum rating of 6.5V and makes radiation noise countermeasures easier.

Moreover, the RM590 can automatically switch its operation mode between VFM (Variable Frequency Modulation) and PWM (Pulse Width Modulation) depending on the load current. This function enables the IC to operate with high efficiency at both heavy and light load.

Features

• Input Voltage Range (Maximum Rating): 2.3 V to 5.5 V (6.5 V)

• Output Voltage (Fixed Output Voltages): from 0.6V to 3.3V in 0.1V increments

• Output Voltage (Adjustable Output Voltages): 0.6 V to 5.5 V 0.6V Reference (VFB), ±9 mV Voltage Accuracy

• Selectable Oscillator Frequency: Typ. 6.0 MHz

• Oscillator Maximum Duty: Min. 100%

• MOSFET ON Resistance (VIN = 3.6 V): High Side MOSFET Typ. 0.245 Ω Low Side MOSFET Typ. 0.225 Ω

• UVLO Detector Threshold: Typ. 2.0 V

• Soft-start Time: Typ. 0.15 ms

• Thermal Shutdown Function: Detection Temperature 140°C

Applications

• Devices need to be miniaturized such as wearables, hearables

• Phones, domestic LAN systems

• Communication modules, and applications for Industrial equipment

• Instrumentation equipment such as flow meters and pressure gauges