The A8600 includes control circuitry to implement three adjustable, asynchronous buck regulators with integrated MOSFETs. It also provides the control circuitry, gate drivers, and current sensing to implement a synchronous buck regulator with external MOSFETs.
Of the three asynchronous regulators, one is an “always on” type of buck regulator that operates down to at least 3.6 V input voltage (with the voltage falling). In standby mode, the “always on” regulator draws less than 50 µA from 12 V while employing pulse frequency modulation (PFM) to deliver 3.3 V at 40 µA via the regulator.
Features of the A8600 include an enable/synchronisation input to either turn the A8600 on and off or increase or decrease the base PWM frequency, four adjustable soft-start times and four external compensation pins. Output voltage monitoring of the three switching regulators is provided by a single, open-drain, “power OK” output.
In addition, the A8600 also incorporates two high-voltage high-side switches with foldback overcurrent protection for passing a voltage while passing a current of up to 450 mA and limiting the current to 100 mA during foldback. The two high-side switches actively block reverse current.
The A8600 also features direct battery and switched accessory battery detectors and a mute pulse output with an adjustable delay. Additional protection capabilities include pulse-by-pulse current limit, “hiccup” mode short-circuit protection, asynchronous diode protection, “boot” voltage protection, undervoltage lockout, overvoltage protection and thermal shutdown.
The A8600KLPTR-T device is available in a 48-pin LQFP package with exposed pad (suffix JP) for enhanced thermal performance.
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