WSH181 Hall Effect Switch IC Features: z Operates from 2.4V to 26V supply voltage with reverse voltage protection z Operates with magnetic fields from DC to 15kHz z On-chip Hall Sensor z On-chip temperature compensation circuitry minimizes shifts in on and off points and hysteresis over temperature and supply voltage z Ideal sensor for speed measurement, revolution counting, positioning, and DC brushless motors z On(L) with magnetic South pole and Off (H) with North pole Functional Description : WSH181 is designed to integrate Hall sensor with output driver together on the same chip, it is suitable for speed measurement, revolution counting, positioning, and DC brushless motors. It includes a temperature compensated voltage regulator, a differential amplifier, a Hysteresis controller and a open-collector output driver capable of sinking up to 20mA current load. An on-chip protection resistor is implemented to prevent reverse power fault. The temperature-dependent bias increases the supply voltage of the hall plates and adjusts the switching points to the decreasing induction of magnets at higher temperatures. Subsequently, the open collector output switches to the appropriate state. WSH181 are rated for operation over temperature range from –40˚ C to 125 ˚C and voltage ranges from 2.4V to 26V. Pin Descriptions: Name P/I/O Vdd P Gnd O Vout O Pin# 1 2 3 Description Positive Power Supply Ground Output Pin Absolute Maximum Rating (at Ta=25˚ C) Supply Voltage Vcc -------------------------Output breakdown Voltage Vout(breakdown) ---------------Magnetic flux density B -------------------------- 26V 30V Unlimited Winson reserves the right to make changes to improve reliability or manufacturability. ©Winson, 2007/7/13 WSH181 Reverse Protection Voltage Vr Output ON Current (continuous) Ic Operating Temperature Range Storage Temperature Range Package Power Dissipation --------------------------------------------------- Ta -------------------------Ts -------------------------Pd -------------------------- 26V 25mA (-40˚C to +125˚C) (-65˚C to +150˚C) 500mw Electrical Characteristics: (T=+25˚C, Vcc=2.4V to 26V) Characteristic Symbol Test Conditions Min Typ Max Units Supply Voltage Vcc V ─ 2.4 ─ 26 Output Saturation Vout Vcc=12V,Ic=10mA ─ V 0.2 0.6 Voltage (sat) B > Bop Output Leakage Ileakage Vcc=12V, B<Brp uA ─ <0.1 10 Current Supply Current Isupply Vcc=12V,Output mA ─ 2.8 8 Open Output Rise Time Tr Vcc=12V,RL=2K 1.0 ─ 10 μs Ω CL=20Pf Output Falling Time Tf Vcc=12V,RL=2K ─ 0.3 1.5 μs Ω CL=20Pf Function Block: Winson reserves the right to make changes to improve reliability or manufacturability. ©Winson, 2007/7/13 WSH181 Magnetic Characteristics: Characteristic Symbol Operating Point Grade Min. Typ. Max. Unit Bop +10 + 60 + 120 Guass Release Point Brp -120 - 60 -10 Guass Hysteresis Window Bhys 120 200 Guass Ordering Information: Package Information: Winson reserves the right to make changes to improve reliability or manufacturability. ©Winson, 2007/7/13 WSH181 SOT23: Winson reserves the right to make changes to improve reliability or manufacturability. ©Winson, 2007/7/13 WSH181 Application Circuit: Fan Application: Magnetic detector: Winson reserves the right to make changes to improve reliability or manufacturability. ©Winson, 2007/7/13