ATS278A-PL-A

ATS278 Two Phase Hall Effect Latch With FG Output Features - On-chip Hall plate - Operating voltage: 3.5V~20V - Internal bandgap regulator allows temperature compensated operations and a wide operating voltage range - High output sinking capability up to 400mA for driving large load - Built-in protection diode only for chip reverse power connecting - Frequency Generation (FG) output - Package: SIP-5L General Description ATS278 is an integrated Hall sensor with two output drivers and rotor speed output, typically designed for electronic commutation of two-phase brush-less DC fan applications. On-chip Hall sensor will generate Hall voltage due to magnetics sensing. The amplifier will amplify the Hall voltage. The Schmitt trigger determines switching hysteresis and then control internal driver’s on/off to sink load current. Meanwhile, An internal bandgap regulator is used to provide stable bais due to temperature-compensation. FG pin will provide switching frequency of driver. Major feature is to minimize the external components by building-in FG output transistor. If a magnetic flux density larger than threshold Bop, DO is turned on (low) and DOB is turned off (high). The output state is held until a magnetic flux density reversal falls below Brp causing DO to be turned off and DOB turned on. Applications - Dual-coil Brush-less DC Motor - Dual-coil Brush-less DC Fan - Revolution Counting - Speed Measurement Ordering Information ATS278 X - X X - X Wafer Body Blank or A~Z : if necessary to specify Package P: SIP-5L Lead L : Lead Free Magnetic Characteristics A or B *Packing: Bulk Typical Application Circuit 5V/12V + C1 Rpu 1 2 3 4 5 278 Coil1 Coil2 Speed R1 = R2 = 47 Ω C1 = C2 = 2.2 μ F The R, C value need to be fine tuned base on coils design. R1 C1 R2 C2 5V/12V DC Brush-less Fan with FG output function This datasheet contains new product information. Anachip Corp. reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sale of the product. Rev. 1.0 1/6 Oct 4, 2005 ATS278 Two Phase Hall Effect Latch With FG Output Block Diagram VCC 2 3 REG. Comparators Hall Plane Amp DO 4 DOB 5 GND 1 FG Pin Configuration 278 ( Front View ) 1 : FG 2 : VCC 3 : DO 4 : DOB 5 : GND 123 45 Name FG VCC DO DOB GND P/I/O O P O O P Pin # 1 2 3 4 5 Description Frequency detection output Positive power input Driver Output Driver Output ( Inverting ) Ground Anachip Corp. www.anachip.com.tw 2/6 Rev. 1.0 Oct 4, 2005 ATS278 Two Phase Hall Effect Latch With FG Output Absolute Maximum Ratings Characteristics Supply voltage Reverse VCC Polarity Voltage Magnetic flux density Continuous Output “on” current Hold Peak (Start Up) Sink current of FG Operating temperature range Storage temperature range Package Power Dissipation Symbol VCC VRCC B Ic IFG Ta Ts PD Values 20 -20 Unlimited 0.4 0.5 0.7 40 -20~+85 -65~+150 550 Unit V V A mA °C °C mW Electrical Characteristics ( Ta=+25°C ) Characteristic Supply Voltage Output Saturation Voltage Output Zener Breakdown Output Leakage Current Supply Current Output Rise Time Output Falling Time Switch Time Differential Symbol VCC Vce(sat) Vz* Icex Icc tr tf ∆t Conditions Vcc=14V, IL=300mA Vce=14V, Vcc=14V Vcc=20V, Output Open Vcc=14V, RL=820Ω, CL=20pF (Test Circuit) Vcc=14V, RL=820Ω, CL=20pF (Test Circuit) Vcc=14V, RL=820Ω, CL=20pF (Test Circuit) Vcc=14V, IL=20 mA Min 3.5 ------------------Typ ---300 46