Allegro Microsystems' A8591 provides all the control and protection circuitry to produce a fixed 5 V or 3.3 V output, 2 A regulator with ±1% output voltage accuracy. The A8591 employs pulse-frequency modulation (PFM) to draw less than 33 μA from 12 VIN while supplying 5 V/40 μA, making it ideal for automotive battery powered "keepalive" applications. The sleep feature drops standby current down to 5 μA.
When operational, the A8591 operates down to at least 3.6 VIN (VIN falling). The regulator's PWM switching frequency can be programmed with a resistor or synchronized to an external clock. The A8591 has external compensation to optimize stability and transient response for a wide range of external components and applications. The A8591 has a fixed soft-start time of 5 ms.
The A8591 is targeted for the automotive market in the following applications: instrument clusters, audio systems, navigation, HUD, ADAS, and HVAC.
The A8591 is supplied in a 10-pin wettable flank DFN package (suffix EJ) with exposed power pad. It is lead (Pb) free with 100% matte-tin leadframe plating.
Features and Benefits
- Automotive AEC-Q100 qualified
- Withstands surge input to 40 VIN for load dump
- Operates down to 3.4 VIN (typ.), 3.6 VIN (max.) for idle stop
- Utilizes pulse-frequency modulation (PFM) for low-IQ mode
- 10 μA sleep mode (automatic PWM/low-IQ PFM mode selection)
- Fixed output voltage options: 3.3 V or 5 V with ±1% accuracy
- Delivers up to 2 A of output current
- Integrated 110 mΩ high-side MOSFET
- Adjustable switching frequency from 300 kHz to 2.4 MHz
- EMI reduction features:
- Frequency dithering
- Controlled switching node
- External synchronization capability
- Maximum duty cycle for low dropout
- Active low NPOR output with 7.5 ms delay
- Pre-bias startup capable: VOUT increases monotonically, will not cause a reset
- External compensation for max. flexibility
- Stable with ceramic or electrolytic output capacitors
- Internally fixed soft-start time of 5 ms
- Pulse-by-pulse current limit, hiccup mode short-circuit, and thermal protections
- Pin open/short and component fault tolerant
- -40°C to +150°C operating junction temperature range
- Thermally enhanced DFN-10 surface-mount package
Applications
- Automotive
- Instrument clusters
- Audio systems
- Navigation
- HVAC
- Home audio
- Network and telecom
- Industrial
