TL7757CD

PMIC – Supervisors

PMIC (power management IC) - Supervisors are used to provide monitoring and protection solutions for microcontroller-based systems. Such systems may contain analog circuits, digital circuits and even mixed-signal circuitry. The TL7757CD is an example of such a PMIC - Supervisor.

TL7757CD Application Field

The TL7757CD is typically used in consumer applications such as notebook and laptop computers, digital cameras, and mobile phones. It provides a low-power, cost-effective supervisor solution that can ensure reliable operation in such products, even in power-down conditions. The TL7757CD also has a wide temperature operating range, from -40°C to +125°C, up to the mid-range and high-power range.

The TL7757CD supervisor provides integrated voltage monitoring and brown-out protection for either single power supply and multiple power supply applications, such as 1-cell Li-Ion /4.2V, 3-cell/12.6V, and 5-cell/21V. In addition, the TL7757CD can detect incorrect power supply polarity, short to GND, short to battery, and over-voltage conditions.

Another application of the TL7757CD is in Li-Ion cell battery pack protection, which offers extra protection for applications with multiple lines of protection, combining battery-connection detect, automatic shutdown, low-battery detect, short-circuit detect and secondary over-voltage detect.

TL7757CD Working Principle

The working principle of the TL7757CD is to protect the external system from various anomalies that can occur during operation, by providing a low-voltage supervisor solution. It does this by detecting when the voltage level of the power supply drops below a predefined threshold level, and then affects the reset pin of the system.

The TL7757CD contains a Level Shifting Voltage Detector (LSVD) and two active-low Power-On Reset (POR) pins with an optional auto-start feature. The LSVD can be triggered by a Brown-out Detect (BOD) circuit, which detects when the input voltage falls below a certain threshold value, and triggers a reset.

When the LSVD is triggered, the POR signals are sent to the external system to initiate a system reset, which is required to protect the system from damage. The auto start feature allows the reset pin to stay active even when the voltage level of the power supply is below the defined trip point. Such a feature is useful in applications that require fast start-up times.

The TL7757CD also provides other features, such as status function, manual reset, and additional protection against power supply and battery failure. All these features make the TL7757CD an excellent choice for systems that require high reliability.