Allegro Microsystems A8654

Description

The A8654 is a high output current synchronous buck regulator that integrates low RDSON high-side and low-side N-channel MOSFETs. The A8654 incorporates PWM current mode control to provide simple compensation, excellent loop stability and fast transient response. The A8654 utilizes external compensation to accommodate a wide range of power components to achieve both excellent loop stability and desirable transient response.

The A8654 regulates nominal input voltages from 4.0 V to 36 V and remains operational when VIN drops as low as 2.6 V. When the input voltage approaches the output voltage, the duty cycle is maximized to maintain the output voltage. The A8654 is able to provide 3 A steady state load current. The A8654’s features include externally set soft-start time, external compensation network, an EN input to enable VOUT, a SYNC/FSET input to synchronize or set the PWM switching frequency, and a NPOR output validated by the output voltage.

Protection features include VIN Undervoltage Lockout (UVLO), cycle-by-cycle Over Current protection, hiccup mode short-circuit protection, Overvoltage protection, and thermal shutdown. A8654 provides open-circuit, adjacent pin short-circuit, and short-to-ground protection at every pin to satisfy the most demanding automotive and non-automotive applications.

The maximum junction temperature is 150°C. The A8654 device is available in a 16-pin eTSSOP package with exposed pads for enhanced thermal dissipation. It is lead (Pb) free, with 100% matte tin lead frame plating.

Features

• Operating voltage range: 4.0 V to 36 V
• UVLO STOP threshold is at 2.6 VTYP
• Maximized duty cycle for low dropout operation
• Withstands surge voltages up to 40 V
• Capable of 3.0 A steady-state output current
• Integrated high-side and low-side switching MOSFETs
• Adjustable switching frequency (fSW): 100 kHz to 2.2 MHz
• Synchronization capability to external clock: 100 kHz to 2.2 MHz
• Frequency dithering for lower EMI signature
• External adjustable compensation network
• Soft start time externally set via the SS pin
• Pre-bias startup compatible
• Active low, Power on Reset NPOR output
• Over voltage protection, cycle-by-cycle current limit, hiccup mode short circuit, and thermal protections
• Open-circuit and adjacent pin short-circuit tolerant
• Short-to-ground tolerant at every pin
• Stable with ceramic output capacitors

Remarks:Table 3: Recommended Components ValuesRefer page no.23

Typical applications

• General 24 V / 36 V Applications
• Automotive Infotainment Systems
• Audio, Video Navigation Systems
• Advanced Driver Assistance Systems
• Telematics
• Vision and Detection Systems
• Rear Seat Media Display
• RADAR, LIDAR, mmWave Systems
• Instrument Clusters
• Industrial

More information

• Datasheet
• IC product information