The A5972D is a step-down monolithic power supply switch regulator with a minimum switching current limit of 1.8 a, so it is capable of providing up to 1.5 a DC current to loads depending on application conditions. Output voltage is available from 1.235V to VIN Settings.
The device uses an internal p-channel DMOS transistor (typical RDS(on) of 250 mΩ) as the switching element to minimize the size of the external components. An internal oscillator fixed the switching frequency at 250 KHZ. With a minimum input voltage of only 4v, it is suitable for automotive applications that require equipment to operate even in cold crank conditions. Pulse to pulse current limit and internal frequency modulation provides effective constant current short-circuit protection.
A5972D Pin connection
A5972D Application schematic
Functional description
● The main internal modules are shown in the device block diagram below. They are:
● Voltage monitoring circuit, used to check the input voltage and internal voltage.
● Fully integrated sawtooth oscillator, the frequency of 250 KHZ ±15%, including braking
● Voltage feedforward feature and input/output synchronization pin.
● Two embedded current limiting circuits control the flow of current power switch. If the current reaches an internal threshold, the pulse-by-pulse current limit will force the power switch off cycle by cycle while the frequency shifter Reduce switching frequency to significantly reduce duty ratio.
● Transconductance error amplifier.
● A pulse-width modulator (PWM) comparator and corresponding logic circuit drive the internal power.
● High side driver for internal P-MOS switches.
● A circuit to achieve thermal protection function
A5972D Block diagram
Features
● Passed AEC-Q100 certification requirements (see PPAP for details)
● 1.5 DC Output current
● Working input voltage is 4v ~ 36v
● 3.3V /(±2%) reference voltage
● Output voltage is adjustable from 1.235V to VIN
● Low difference work: duty cycle 100%
● 250 KHZ internal fixed frequency
● Voltage feedforward
● Zero load current operation
● Internal current limiting
● Inhibit zero current consumption
● Prevent feedback disconnection
● Hot shutdown
Applications
● Focus on automotive applications
