MAX709LCSA+

Due to market price fluctuations, if you need to purchase or consult the price. You can contact us or emial to us:   sales@allicdata.com

Power management is an essential component of any electronic system. In order for a system to operate properly, the power needs to be delivered and regulated to all of the components in the system. A power management integrated circuit (PMIC) is a chip that contains multiple power management functions within it. PMICs include voltage regulators, power switches, battery chargers, and supervisor circuits. PMICs are well-suited for applications that require tight voltage/current regulation and/or power sequencing to ensure that the system operates safely.

The MAX709LCSA+ is a dual-voltage supervisor IC from Maxim Integrated that combines two voltage supervisors, a shunt voltage regulator, a loss-of-signal detector, and a power-good indicator. This device provides reliable power-on reset (POR) and power-fail reset (PFR) functionality. It is available in an 8-pin SOT-23 package and is designed to be used in space-constrained applications such as cell phones, PDAs, digital cameras, medical devices, automotive, and industrial systems.

Application Field

The MAX709LCSA+ is designed to provide reliable reset in low standby-mode power systems where excellent noise immunity is required. It offers a reset duration of up to 500 ms for the POR function. The PFR function monitors power supply voltage levels to detect over-voltage and under-voltage conditions. It also provides a low quiescent current of 10 μA at room temperature. This makes it suitable for battery-powered applications as well as systems powered from USB/3V3 sources.

The MAX709LCSA+ also provides an adjustable Schmitt-triggered input for monitoring external watchdog or loss-of-signal (LOS) functions. In addition, it can be used to detect system faults, such as a failed battery. The IC offers a power-good output that can be used to indicate supply voltage conditions and the reset status. This output can be used to drive an LED or to control a logic circuit.

Working Principle

The MAX709LCSA+ is designed to monitor the main system power supply or an auxiliary power supply. Upon power-on, the MAX709LCSA+ will generate a 16 ms reset pulse. After power-on, the device will continuously monitor the main and auxiliary power supplies. If the main supply falls below the POR threshold of 2.6 V (typical) or the auxiliary supply falls below 1.2 V (typical), a reset pulse will be generated.

The MAX709LCSA+ has an active-low power-good output that is used to indicate the status of the main and auxiliary power supplies. The PGOOD pin will remain low until both supplies reach the VOK_L and VOK_H thresholds. The PGOOD output will go high once the VOK_H and VOK_L thresholds have been reached. The PGOOD output will stay high as long as both supplies remain within the specified thresholds. If either supply falls out of the specified threshold range, the PGOOD pin will go low, indicating a power-fail condition.

The reset output of the MAX709LCSA+ is active-low and should be connected to the system reset input. When a voltage-fail or low-power condition is detected, the reset output will remain low until the supply voltage is within the specified threshold. The reset output pin will go high one-shot once the threshold is met. This ensures that the reset circuit is not affected by any short-term noisy supply conditions.

Conclusion

The MAX709LCSA+ is a dual-voltage supervisor IC designed to provide reliable reset functions in low-power, space-constrained applications. It offers POR and PFR functions as well as an adjustable Schmitt-triggered input for monitoring watchdog or loss-of-signal signals. The MAX709LCSA+ can be used to detect system faults such as a failed battery. The integrated power-good output can be used to indicate the reset status and supply conditions.

The specific data is subject to PDF, and the above content is for reference