STMicroelectronics A6983I

The A6983I is a device specifically designed for isolated buck topology. The primary output voltage can be accurately adjusted, whereas the isolated secondary output is derived by using a given transformer ratio. No optocoupler is required. The primary sink capability up to -4.5 A (even during soft-start) allows a proper energy transfer to the secondary side, as well as enables a tracked soft-start of the secondary output. The control loop is based on a peak current mode architecture and the device operates in forced PWM. The 390 ns blanking time filters oscillations, generated by the transformer leakage inductance, makes the solution more robust.

Both the compact QFN-16 (3x3 mm) package and the internal compensation of the A6983I help minimizing the design complexity and size.

The switching frequency can be programmed in the 200 kHz to 1 MHz range with an optional spread spectrum for improved EMC.

The EN pin provides a enable/disable functionality. The typical shutdown current is 2 μA when disabled. As soon as the EN pin is pulled-up, the device is enabled and the internal 1.3 ms soft-start takes place. The A6983I features a Power Good open collector that monitors the FB voltage. Pulse by pulse current sensing on both power elements implements an effective constant current protection and thermal shutdown prevents thermal runaway.

Features

• AEC-Q100 qualified
• Operating temperature range: -40 °C to +150 °C for T_j
• Designed for iso-buck topology
• 3.5 V to 38 V operating input voltage
• Load dump tolerant up to 40 V
• Primary output voltage regulation, no optocoupler required
• 4.5 A source/sink peak primary current capability
• Peak current mode architecture in forced PWM operation
• 390 ns blanking time
• 25 μA operating quiescent current
• 200 kHz to 1 MHz programmable switching frequency, stable with low ESR capacitor: min 2 µF
• Internal compensation network
• 2 μA shutdown current
• Internal soft-start
• Enable pin
• Overvoltage protection
• Output voltage sequencing
• Thermal protection
• Optional spread spectrum for improved EMC
• Power Good
• Synchronization to external clock
• QFN16 (3x3 mm) package

STSW-eDSim - fast and powerful electrical simulation software for SMPS and analog ICs

eDSim is a fast and powerful electrical simulation tool for SMPS and analog ICs, integrated in the eDesignSuite tool. It features enhanced accuracy and higher convergence speed for SMPS, enabling a simulation time 10-50x faster than the classical analog SPICE simulators.

The tool is a specific version of the SIMPLIS/SIMetrix simulation environment paired with ST model components, for a full electrical simulation with no limitation of nodes and circuit size.

Design your analog circuit using the eDesignSuite engine, display a preview of it in few seconds with full annotated schematic and BOM, and then run the electrical simulation through eDSim to get fast and accurate simulations and reliable design validation, thus reducing the effort and risks related to hardware prototyping.

With the eDSim tool you can also create your schematic from scratch using ST models or simulate your SMPS and analog ICs from a list of predefined ST application schematics - test benches, that you can partially modify according to your needs.

Software release 2024.12 is now available.

Features

• Built-in interface with eDesignSuite
• SMPS circuit full modeling using ST components
• Time domain simulation
• Control loop stability
• Predefined application use-case simulation
• Schematic editor for customization
• Waveform viewer with measurement capabilities

STEVAL-A6983IV1 - 38 V, 10 W synchronous iso-buck converter for isolated applications

The STEVAL-A6983IV1 is an evaluation board based on the A6983I, 38 V, 10 W synchronous iso-buck converter designed for isolated applications.

The primary output voltage can be accurately adjusted, whereas the isolated secondary output is derived by using a given transformer ratio. No optocoupler is required.

The primary sink capability up to -4.5 A (even during soft-start) allows a proper energy transfer to the secondary side as well as enables a tracked soft-start of the secondary output.

The control loop is based on a peak current mode architecture and the device operates in forced PWM.

The 390 ns blanking time filters oscillations, generated by the transformer leakage inductance, making the solution more robust.

The compact QFN-16 3x3 mm package and the internal compensation of the A6983I help minimizing design complexity and size.

The switching frequency can be programmed in the 200 kHz - 1 MHz range with optional spread spectrum for improved EMC.

The EN pin provides enable/disable functionality. The typical shutdown current is 2 uA when disabled. As soon as the EN pin is pulled up, the device is enabled and the internal 1.3 ms soft start takes place.

The A6983I features a power-good open collector that monitors the FB voltage. Pulse by pulse current sensing on both power elements implements an effective constant current protection and thermal shutdown prevents thermal runaway.

Due to the primary reverse current limit, the secondary output is protected against short-circuit events.
 

BUY NOW AT FARNELL

BUY NOW AT FARNELL