AH5792-ZG-7 Diodes Incorporated

AH5792 SINGLE PHASE HALL EFFECT LATCH SMART FAN MOTOR CONTROLLER Description Pin Assignments The AH5792 is a single chip solution for driving single-coil ( Top View ) brush-less DC fans and motors. The AH5792 employs a 1 5 O2 FG bidirectional full bridge driver output stage for single coil fan motor applications. The device includes features such as 2 Rotor Lock Protection with rotor lock detection and automatic V NC SS self-restart to avoid damage to the coil when the rotor is blocked. 3 4 O1 Vdd SOT553 The AH5792 also offers an externally controlled Tachometer (Frequency Generator Pin) open -drain output which makes it easier to connect with external interface such as hardware ( Top View ) monitoring. The FG is half (1/2) the magnetic change frequency. O2 1 5 FG The devices are packaged in SOT553 and SOT89-5L small NC 2 Vss outline packages for applications such as small motors like vibration motors or ultra thin cooling fans. O1 3 74 Vdd SOT89-5L Features Applications 3.3V / 5V Min. DC Fans (Eight Pole) Support single-phase full wave min fan driver Low Voltage / BLDC Motors Built-in Hall sensor input amplifier Micro-Vibration Motors Low voltage startup ( Vdd=1.8V ) Lock detection and automatic self-restart Without external timing capacitor, Reduces the numbers of external component required FG output Low profile package : SOT553 and SOT89-5L Green Molding Compound 1 of 10 July 2010 AH5792 Diodes Incorporated www.diodes.com Document number: DS314641 Rev. 6 - 2 AH5792 SINGLE PHASE HALL EFFECT LATCH SMART FAN MOTOR CONTROLLER Typical Application Circuit (Note 1) SYSTEM POWER 10Kohm SYSTEM V FG FG dd POWER D1 C1 Dz O1 AH5792 O2 V SS Notes: 1. Reverse connection of power supply may break the device. A countermeasure is needed such as using reverse power protection diode D1 between power supply and Vdd terminal. In such case of using reverse power protection diode D1 because of there is no way to return current to power supply, please take necessary measures like below. - Connect Dz (Zener diode) between Vdd and Vss terminal, not to exceed the absolute maximum rating voltage. - Connect a capacitor C1 between Vdd and Vss terminal, to make the path of return current to power supply. The AH5792 has an open-drain tachometer FG output that follows the half (1/2) the magnetic change frequency. A pull-up resistor (10Kohm, typically for System Power = 5V) connected to a supply voltage. Pin Descriptions (Note 2) Pin Name Description O1 Output driving & sinking pin 1 Vdd Power supply pin Vss Ground pin FG Frequency Generator (Note 2) O2 Output driving & sinking Pin 2 NC No Connection Notes: 2. The FG is half (1/2) the magnetic change frequency. 2 of 10 July 2010 AH5792 Diodes Incorporated www.diodes.com Document number: DS314641 Rev. 6 - 2