BD4728G-TR Integrated Circuits (ICs)

PMIC - Supervisors control the start-up sequence and other characteristics of electronic devices, as well as monitoring and protecting electronic devices by detecting overcurrent fault conditions. The BD4728G-TR designed by ROHM Semiconductor is a Low Power Supervisory Circuit with delay resumed reset. This Reset IC is ideal for use in microprocessor-systems where a watchdog timer and reset signal are necessary.

Features of BD4728G-TR

This IC features low power consumption, a wide reset hold-off range and a 50mA rating for external circuit currents. It also combines reset assertion with a low-power watchdog timer. The watchdog timer circuit works as an emergency-boot system protector for various microprocessor systems. It has an input/output temperature range of -40C to 85C, and is available in a SOT-23-6 package.

The device employs an NMOS-FET output to supply the reset output signal. Its input is a one-time programmable voltage detector with a detection voltage range of 1.02V. The detection voltage remains constant across process spread. It also has an adjustable period time over a wide range of 100ms to 8s. The adjustable period time is critical in providing reliable operation, as it can be programmed to provide an accurate warning before the device goes into a reset condition.

Application Field of BD4728G-TR

The BD4728G-TR has found wide use in information communication equipment that require high reliability and low-power consumption such as computing platforms and embedded boards. It is ideal for portable and mobile devices, such as PDAs, tablet PCs, and smart phones. This reset IC also finds use in various home and industrial appliances, including air conditioners, refrigerators, and medical equipment.

Working Principle of BD4728G-TR

The BD4728G-TR is designed to detect and protect system failures caused by over-voltage, under-voltage, and over-current fault conditions. It works by monitoring an input voltage with an internal one-time programmable voltage detection circuit. If the voltage drops below the detection voltage, the reset signal will be asserted due to a non-existing or incorrect reset condition. This device also implements a watchdog timer, which is reset or hold-reset based on the external reset signal status. The timer is reset internally when the voltage detects a valid reset signal. If no reset signal is detected, it will generate a reset signal after a fixed interval when an internal counter reaches the watchdog timeout value.

Additionally, the delay resumed reset feature helps prevent the reset from occurring due to an input voltage fluctuation. It works by resuming the reset signal after a certain period of time has elapsed. This feature prevents system malfunctions from occurring due to false reset signals, and improves system stability.

The BD4728G-TR is a low-power Supervisory Circuit with delay resumed reset, and is especially suitable for various microprocessor-systems where a watchdog timer and reset signal are necessary. It’s adaptive reset signal and adjustable period time provide a reliable emergency system protection, while its low-power consumption is ideal for use in portable and mobile devices. With applications ranging from computing platforms to medical equipment, the BD4728G-TR is a versatile and reliable solution for monitoring and protecting electronic devices.