MA2001 MPOWER | Alldatasheet

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1.4A Boost for White LED Driver  GENERAL DESCRIPTION The MA2001 is a high frequency, asynchronous boost converter. T he internal MOSFET can support up to 8 White LEDs for backlighting and OLED power ap plication, and the internal soft start function can reduce the inrush current. The MA2001 uses current mode, 1.0MH Z fixed frequency architecture to regulate the LED current, which is set through an external current sense resistor . Its low 300mV feedback voltage reduces power loss and improves efficiency. The OVP p in monitors the output voltage and turns off the converter if an over-voltage condition i s present due to an open circuit condition. The MA2001 includes under-voltage lockout, current limiting and thermal shutdown protection preventing damage in the event of an output overload. The driver is available in small 6-pin SOT23 & TSOT23 packages.  FEATURES - 2.5V to 5.5V operating input voltage range - Drives up to 8 series White LEDs - 1.0MHz Fixed Switching Frequency - Wide range for PWM dimming (200Hz to 200KHz) - Internal 1.4A switching current limit - Over Voltage Protection (OVP) - Internal Soft-start Function - Current limit and Thermal shutdown protection - Under voltage Lockout APPLICATIONS - Cellular Phones - Digital Cameras - Tablet PC and Handheld Computers - PDA, DVD and GPS Receivers - Portable Instruments

 BLOCK DIAGRAM GND OVP OSCILLATOR COMP ILIMIT EA REFERENCE and BIAS SOFTSTART EN FB SW VCC Thermal Shutdown OVP Current Sense PWM CONTROL LOGIC UVLO and POR Enable Logic DRIVER 10ms LPF Shutdown  PIN ASSIGNMENT The package of MA2001 are SOT23-6L & TSOT23-6L ; the pin assignment is given by: Name Description VCC Power Input Pin GND Ground Pin. FB Feedback Pin. EN Chip Enable & Dimming pin. Active high. Internal pull low. OVP Over voltage detect pin SW Switching Pin  ORDER/MARKING INFORMATION Order Information Top Marking

 ABSOLUTE MAXIMUM RATINGS (at TA=25°C) Characteristics Symbol Rating Unit VCC pin voltage VIN -0.3 to 6 V SW pin voltage VSW -0.3 to 33 V OVP pin voltage VOVP -0.3 to 33 V EN, FB pins voltage -0.3 to VIN+0.3 V Continuous Power Dissipation PD ( TJ-TA ) / θJA mW Operating Junction Temperature Top -40 to 125 °C Storage Temperature Range -65 to 150 °C Thermal Resistance from Junction to case θJC 180 °C/W Thermal Resistance from Junction to ambient θJA 250 °C/W Note: θJA is measured with the PCB copper are (need connect to GND of the MA2001) of approximately 1 in2 (Multi-layer).  ELECTRICAL CHARACTERISTICS (VIN = 5V, VEN = 5V, IOUT = 20mA, TA = 25°C) Characteristics Symbol Conditions Min Typ Max Units Input Voltage Range VIN 2.5 - 5.5 V Input UVLO UVLO Rising - 2.25 2.45 V UVLO Hysteresis - 0.1 - V OVP Sense Voltage VOV 27.5 29 - V Quiescent Current ICCQ VFB = 0.5V , IOUT = 0mA - 200 400 μA Supply Current IIN VFB = 0V , Switching - 1 2 mA Shutdown Current ISD VEN = 0V , TEN > 20mS - 1 4 μA FB Pin Voltage VFB 0.285 0.300 0.315 V FB Pin Current IFB - - ±100 nA Load Regulation 1mA < IOUT<20mA - 1 - % Line Regulation 3V<VIN<4.3V - 1 - % EN Pin Voltage High VENH 1.4 - - V EN Pin Voltage Low VENL - - 0.4 V EN Hysteresis - 0.1 - V

EN Pin sink Current IIH - 1 - μA Switching Frequency FOSC 0.75 1 1.25 MHz N-Channel MOSFET Current Limit (Note1) CL - 1.4 - A CL Duty on 50% - 1.9 - A Switching Maximum Duty Dmax - 92 - % Dimming clock rate 0.2 - 200 KHz N-Switch RDS(ON) RDS(ON)-N Vin=3.6V - 0.5 1.0 Ω Thermal Shutdown TSD - 155 - °C Thermal Shutdown Protection hysteresis TSH - 25 - °C Note1: Guaranteed by design.  APPLICATION CIRCUIT  FUNCTION DESCRIPTION Setting the ILED Current output version. The external resistor sets the LED output current according to the following equation: ILED RSET 20mA 15Ω 6mW 350mA 0.857Ω 105mW

Under Voltage Lockout (UVLO) To avoid mis-operation of the device at low input voltages an under voltage lockout is included that disables the device, if the input voltage falls below (2.25V-100mV). Over Voltage Protection OVP measure the output voltage for open circuit protection. Con nect OVP pin to the output at the top of the LED string. If V OUT above 36V, the OVP protection is happened that stops the internal driver until VOUT below 36V. Input Capacitor Selection The input capacitor reduces the surge current drawn from the i nput and switching noise from the device. The input capacitor impedance at th e switching frequency shall be less than input source impedance to prevent high frequency switching current passing to the input. A low ESR input capacito r sized for maximum RMS current must be used. Ceramic capacitors with X5R or X7R diel ectrics are highly recommended because of their low ESR and small temperature c oefficients. A 2.2uF ceramic capacitor for most applications is sufficient. For a low er output power requirement application, this value can be decreased. Output Capacitor Selection The output capacitor is required to keep the output voltage ripple small and to ensure regulation loop stability. The output capacitor must have low impedance at the switching frequency. Ceramic capacitors with X5R or X7R dielect rics are recommended due to their low ESR and high ripple current. A 1uF ceramic capacitors works for most of the applications. Higher capacitor values can be used to improve the load transient response.

PACKAGE OUTLINES (1) TSOT23-6L e b D y R C θ Symbol Dimensions in Millimeters Dimensions in Inches A1 0.00 - 0.10 0 - 0.004 e 0.95 BSC. 0.037 BSC. e1 1.90 BSC. 0.075 BSC. L1 0.60 REF. 0.024 REF. L2 0.25 BSC. 0.010 BSC. θ 0o - 8o 0o - 8o JEDEC outline: MO-193 AA

(2) SOT23-6L L E1 E D b A DETAL A e GAUGE PLANE C DETAL A Symbol Dimensions in Millimeters Dimensions in Inches A 1.05 - 1.45 0.041 - 0.057 A1 0.05 - 2.15 0.002 - 0.085 b 0.30 - 0.50 0.012 - 0.020 C 0.08 - 0.22 0.003 - 0.009 L 0.30 - 0.60 0.012 - 0.024 θ 0o 4o 8o 0o 4o 8o