www.austriamicrosystems.com/Power-Management/AS1390

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AS1390A, AS1390B

Datasheet - D e t a i l e d D e s c r i p t i o n

8.2 Buck Converter

The buck converter of the AS1390 is working with high-efficiency at a constant-frequency. The buck converter is optimized to supply a C and

with a fixed output voltage of 5V.

The buck converter is working as soon as the AS1390 is powered-up but offers an automatic power save mode. The highly efficient duty cycle

provides low dropout operation, which reduces the power consumption of the system.

8.3 Overvoltage Protection (OVP)

An overvoltage condition is detected when the feedback voltage is higher than the skip threshold (1.28V typ.). The device is than entering the

skip mode. Meaning the next pulse will be skipped and in the next cycle the overvoltage check is done again.

8.4 Overcurrent Protection (OCP)

An overcurrent comparator is monitoring the output current via the sense pin. If an overcurrent condition occurs the transistor will be switched off

immediately. After the overcurrent condition is removed the device is returning to normal operation again.

8.5 Overtemperature Protection (OTP)

As soon as the junction temperature reaches approximately 140°C the AS1390 goes in thermal shutdown. In this mode the internal transistors

are turned off. The device will power up again, as soon as the temperature falls below +110°C again.