New Industry Products

ROHM’s Zero-Cross Detection ICs and Maxim’s Essential Analog ICs

October 10, 2020 by Alessandro Mascellino

In this integrated circuits recap, we take a look at integrated zero-cross detection ICs from ROHM and essential analog temperature sensor ICs from Maxim Integrated.

This recap showcases two different types of integrated circuits, respectively from ROHM and Maxim Integrated.


Integrated Zero-Cross Detection ICs From ROHM

ROHM’S new BM1ZxxxFJ Series has been designed to enhance home appliances with IoT capabilities.

In order to communicate with routers, smart home appliances need to be able to always remain ON while retaining low standby power consumption levels.

Many of these devices require a zero-cross detection circuit for detecting the 0V point of the AC waveform in order to provide efficient control of motors and MCUs.


Image used courtesy of ROHM.
Image used courtesy of ROHM.


Traditional zero-cross detection circuits utilize a photocoupler that accounts for nearly half of standby system power, constantly consuming a considerable amount of energy. 

To solve this issue, ROHM has now built these integrated zero-cross detection ICs that do not use a photo-coupler, thus reducing standby current consumption and increasing long-term reliability.

The BM1ZxxxFJ Series can reduce the standby power consumption of the zero-cross circuit to just 0.01W while powering the system, and its error in delay time is limited to ±50µs or less.


Image used courtesy of ROHM.
Image used courtesy of ROHM.


The new components are compatible with input voltages up to 600V and can perform voltage division to the output below the maximum rated voltage of MCU and drive standard MCUs up to 5V.

ROHM has also equipped the BM1ZxxxFJ Series with a voltage clamp function to ensure the input voltage does not exceed 4.8V.

The function is intended to protect the MCU when abnormal voltages are generated in high voltage drive applications like air conditioners.

The BM1ZxxxFJ Series is already available, priced from $0.98 per sample.


Essential Analog Temperature Sensor ICs From Maxim

Maxim unveiled two different products related to analog temperature sensor ICs: the MAX31889 and the MAX31825,

The former is built for temperature monitoring of cold-chain assets, while the latter aims to reduce the complexity of using multiple temperature sensors for consumer and factory automation.

The MAX31889 features precision measurement of ±0.25-degree Celsius accuracy from -20°C to +105°C and ±0.65°C Accuracy from -40°C to +125°C.

Offered in a 6-pin µDFN package, this integrated circuit has a long battery life, with an operating voltage of 1.7V to 3.6V and operating current during measurement of 68µA.


Image used courtesy of Maxim.
Image used courtesy of Maxim.


The MAX31889 also offers a 32-word FIFO for the temperature data and as well as both high and low threshold digital temperature alarms.

The MAX31825, on the other hand, is built to simplify systems’ designs by allowing multiple devices in space-constrained applications.

The IC offers the ability to connect up to 64 programmable devices via the same parasitically powered 1-Wire bus, with the precision of ±1-degree Celsius accuracy.


Image used courtesy of Maxim.
Image used courtesy of Maxim.

The MAX31825 comes in a 6-bump WLP and features a power supply voltage range from 1.6V to 3.6V for external power supplies, and from 2.3V to 3.6V for parasite power. 

The components also extend operational uptime with a low standby current of 2.5µA, which is ideal for consumer devices and factory automation applications.

What new integrated circuits have you noticed this past week? Let us know your thoughts in the comments.