A4406 Datasheet | Allegro MicroSystems

Constant On-Time Buck Regulator with External and Internal Linear Regulator Features AND BENEFITS - AEC-Q100 Grade 0 qualified - Internal buck pre-regulator followed by LDO outputs - 5.5 to 36 V VIN operating range (50 V maximum); for start/stop, cold crank, and load dump requirements - 2.2 MHz constant on-time buck regulator - 50 V absolute maximum input voltage for surges - Valley current sensing achieves shortest buck on-times - 5.5 to 46 V input voltage range - - 40°C to 150°C junction temperature range - Power-on reset (NPOR pin) with adjustable rising delay - 5 V (V5P pin) internal low dropout tracking linear regulator with both overcurrent foldback and short-to-battery protection - 3.3 V (V33 pin) external linear regulator DMOS driver with a programmable current limit (up to 500 m A) and overcurrent foldback protection Continued on the next page… PACKAGE: 20-pin TSSOP with exposed thermal pad (suffix LP) Not to scale DESCRIPTION The A4406 is an automotive power management IC that uses a high frequency constant on-time 5.45 V pre-regulator to supply an internal 5 V linear regulator and a 3.3 V linear DMOS driver. Designed to supply CAN and microprocessor power supplies in high temperature environments, the A4406 is ideal for under hood applications. Efficient operation is achieved by using a buck pre-regulator to efficiently drop the input voltage before supplying the linear regulators; this reduces power dissipation and increases overall regulator efficiency. The switching regulator is capable of operating at a nominal switching frequency of 2.2 MHz. The high switching frequency enables the customer to select low value inductors and ceramic capacitors while avoiding EMI in the AM frequency band. Protection Features include undervoltage lockout and thermal shutdown. The V5P output is protected from short-to-battery events. In case of a shorted load, all regulators feature overcurrent Continued on the next page… APPLICATIONS: Automotive Control Modules,...