Ideal for Applications with Long Sleep Periods,
New Release of the NC4650 Series, a Boost Switching Regulator

- Industry-Leading Ultra-Low Quiescent Current of Iq = 70 nA Achieves High Efficiency at Light Loads -

Nisshinbo Micro Devices Inc. released the NC4650 series, a boost switching regulator for use in consumer applications.

Advances in IoT technology and market expansion have led to an increase in the number of devices with data communication capabilities. In particular, many small IoT devices, security devices, and sensors for industrial equipment are powered by primary batteries, and low power consumption is required to extend battery life. Especially, power consumption during sleep mode has become an issue. In addition, noise reduction is required to prevent transmission errors during data communication.

This product achieves an ultra-low quiescent current of Iq = 70 nA (reduced to 1/4 of our conventional product) and contributes to longer battery life and equipment operation through highly efficient power conversion in sleep mode. It also features a "low ripple mode" for noise reduction, which can be easily switched via the MODE pin. The low ripple and excellent load transient response characteristics suppress transmission errors during data communication. In addition, the PWM/PFM auto-switching control method is used to achieve efficient power supply by automatically switching to PFM when the load current is low and to PWM when the load current becomes high.

The EN pin can be used to switch to the shutdown state with Iq = 50 nA. The operation at the shutdown state can be selected from the following three versions.

• V_IN – V_OUT Complete Disconnect: NC4650ZAxxxAE2S, NC4650ZAxxxCE2S
• V_OUT Discharge (Auto Discharge Function): NC4650ZAxxxBE2S
• V_IN – V_OUT Pass-Through (Seamless Pass-Through Function): NC4650ZAxxxDE2S

The product uses the ultra-small WLCSP-6-ZA1 package (1.3 × 0.92 × 0.4 mm), which is suitable for high-density mounting.

Features

1. Switching between Low Quiescent Current Mode and Low Ripple Mode via MODE Pin

The product has the MODE pin to switch between normal mode with low quiescent current and low ripple mode depending on the operating conditions.
Normal mode achieves high efficiency power conversion (>90%) even at light loads thanks to very low quiescent current (at V_IN = 3.0 V, V_OUT = 3.3 V, I_OUT = 0.01 mA).
Low ripple mode provides low ripple and improved load transient response, making it ideal for noise-sensitive systems.

2. Seamless Pass-Through Function (NC4650ZAxxxDE2S)

The product offers a version that features seamless pass-through during the shutdown state.
The seamless pass-through function outputs the voltage of the VIN and SW pins as they are to the VOUT pin, while suppressing voltage fluctuations on the VOUT pin and reverse current to the SW pin during pass-through.
After the product is switched to the shutdown state by a “high” level control signal input to the EN pin, the output voltage drops due to the load. When the output voltage drops to the voltage of the VIN pin, the output voltage continues to be as the voltage of the VIN pin. 

Applications

• Hearing Aids, Medical Patches
• Smartwatches
• IoT Edge Devices
• Keyless Entry Systems
• Alarms, Wireless Sensor Networks

Product Photo

NC4650 Series, WLCSP-6-ZA1 (1.3 × 0.92 × 0.4 mm)

Main Specifications (Please refer to the datasheet for details.)

Contact