Allegro MicroSystems A8590KLPTR-T-2

Overview

A8590KLPTR-T-2 from Allegro MicroSystems is an automotive-grade asynchronous buck regulator delivering up to 3.0 A output current with ±1.0% output voltage accuracy (0°C to 85°C), 4.0–35 V input range, and programmable 250 kHz–2.4 MHz switching frequency. It integrates a 110 mΩ high-side MOSFET and supports Low-IQ PFM mode drawing ≤50 µA at 12 V_IN/3.3 V_OUT/40 µA load-enabling keep-alive power for car audio microcontrollers during stop-start cycles.

For engineers reviewing the A8590KLPTR-T-2 datasheet, A8590KLPTR-T-2 pinout, A8590KLPTR-T-2 application, or A8590KLPTR-T-2 equivalent, key selection criteria include its AEC-Q100 qualification, 40 V surge tolerance, NPOR open-drain reset output, SLEEP pin ultra-low shutdown (<10 µA), and external synchronization capability via PWM/PFM pin.

Technical Context

The A8590KLPTR-T-2 employs current-mode control with transconductance error amplifier (750 µA/V typ), slope compensation scalable with f_OSC, and pulse-by-pulse overcurrent protection triggering at 4.1–5.1 A. Its Idle/Stop-Start Recovery technique actively suppresses output overshoot during VIN recovery from undervoltage events.

It features dual-mode operation: PWM mode (fixed-frequency, up to 2.4 MHz) and Low-IQ PFM mode (variable-frequency, <50 µA quiescent current), selected via dedicated logic-level PWM/PFM pin. The SLEEP pin forces full shutdown with <5 µA draw at 85°C and 16 V_IN, while NPOR provides active-low power-on reset validated by regulated V_OUT.

Key Specifications

Pinout & Package

Package: 16-pin TSSOP with exposed thermal pad (LP), lead-free, matte-tin plated. Requires minimum 6 vias connecting pad to internal ground plane for thermal performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar buck regulator applications.

Compared with MPQ4333GQ-AEC1-Z and TPS54332QPWPRQ1, the A8590KLPTR-T-2 uniquely combines AEC-Q100 qualification, sub-50 µA PFM quiescent current, integrated NPOR, and SLEEP-controlled shutdown-making it optimal for automotive infotainment subsystems requiring guaranteed boot integrity and extended park-mode battery life.

Availability

A8590KLPTR-T-2 is available at Aetrix Electronics and suitable for automotive instrument clusters, car audio systems, and HVAC control units requiring stable component supply with AEC-Q100 compliance and long-term lifecycle support.

Supply support for A8590KLPTR-T-2 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Allegro MicroSystems is a U.S.-based semiconductor company specializing in high-performance power ICs, magnetic sensors, and motor driver solutions for automotive and industrial markets.

The A8590 product line was designed specifically for next-generation automotive infotainment and body electronics, emphasizing ultra-low quiescent current, robust transient response, and comprehensive fault protection under harsh vehicle electrical environments.

FAQ

What is the minimum input voltage required for the A8590KLPTR-T-2 to maintain regulation?

The A8590KLPTR-T-2 maintains regulation down to 3.4 V_IN (typical) when VIN is decreasing, with UVLO stop threshold specified at 3.2–3.6 V. This enables reliable operation during automotive cold-crank events where battery voltage dips below 6 V. The device continues switching until VIN falls below the UVLO threshold, after which it shuts down cleanly. Full functionality resumes once VIN rises above the UVLO start threshold (3.6–4.0 V).

Does the A8590KLPTR-T-2 support pre-biased startup?

Yes, the A8590KLPTR-T-2 supports pre-biased startup: it will not force V_OUT low or cause a reset when powered into a pre-charged output rail. This behavior is confirmed in the Functional Description section and enables safe integration into multi-rail systems where sequencing is managed externally. The NPOR output remains asserted until V_OUT stabilizes within regulation, regardless of initial bias condition.

How does the A8590KLPTR-T-2 handle output overvoltage conditions?

The A8590KLPTR-T-2 provides hardware-based V_OUT overvoltage protection (OVP) with a PWM-mode threshold of 860–902 mV at FB, corresponding to ~108% of nominal V_OUT. When triggered, it immediately disables the high-side MOSFET and pulls COMP and SS low. The OVP has 10 mV hysteresis to prevent chatter. This protection operates independently of the feedback loop and is effective even during startup or fault conditions.

Can the A8590KLPTR-T-2 be synchronized to an external clock?

Yes, the A8590KLPTR-T-2 supports external synchronization: applying a clock signal >1.2× the base f_OSC to the PWM/PFM pin forces the PWM frequency to lock to the incoming clock rate (up to 2.9 MHz). The sync input requires 200 ns minimum pulse width, 10–15 ns rise/fall times, and ≤80% duty cycle. This feature eliminates switching frequency beat notes in sensitive audio and RF subsystems.

What thermal derating applies to the A8590KLPTR-T-2 at 125°C ambient?

At 125°C ambient, the A8590KLPTR-T-2's output current must be significantly derated due to thermal limits. With R_θJA = 34°C/W on a JEDEC 4-layer board and T_J(max) = 150°C, the allowable temperature rise is only 25°C - limiting continuous output current to ~1.2 A at 12 V_IN/5 V_OUT. For full 3.0 A operation, ambient must remain ≤85°C or PCB thermal design must improve heat spreading via additional copper area and vias to internal planes.