Batteries and Portable Power

0.3µA IQ 300mA Buck-Boost DC-DCs with Synchronous Rectifier

The RP604 from Ricoh is a buck-boost converter featuring a minimum supply current and a high efficiency at low-load. The device operates at the low operating quiescent current (IQ = 0.3 µA) to make the most of battery life especially in devices that are operated intermittently.

In addition to a low quiescent current of 0.3 µA, these buck-boost dc-dc converters have an input voltage range of 1.8V to 5.5V and can support a variety of input sources from a coin-type battery to a USB port. The RP604 is offered in two package styles, WLCSP-20-P2 or DFN(PLP)2730-12

Target applications include: wearable devices such as smart watches, smart bands, healthcare devices; Li-ion / coin battery-powered equipment; low-power wireless communication equipment such as Bluetooth® Low Energy, ZigBee, WiSun, ANT, and so on; and low-power devices for CPU, memory, sensors, energy harvesting, etc.

The set output voltage, the auto-discharge function and the package are user-selectable options. The set output voltage (VSET) is offered within the range of 1.6V to 5.2V in 0.1V steps.

The auto-discharge function quickly lowers the output voltage to 0 V, when the chip enable signal is switched from the active mode to the standby mode, by releasing the electrical charge accumulated in the external capacitor.

RP604 block diagram

Key specifications include:

  • Input Voltage: 1.8V to 5.5V
  • Output Voltage: 1.6V to 5.2V, in 0.1V steps
  • Output Voltage Accuracy: ±1.5%
  • Maximum Output Current: 300mA at Buck
  • Built-in Driver On-resistance (RP604Z, VIN = 3.6V): PMOS = Typ.0.12Ω, NMOS = Typ. 0.12Ω
  • Operating Quiescent Current (IQ ): 0.3µA
  • Standby Current: 0.01µA
  • Protection Features: UVLO, OVP, LX Peak Current, and Thermal Shutdown