Boost LED Driver IC MH9335 Description Features MH9335 is a high efficient boost type LED Wide LED current range: 5mA to 2A driver IC. Wide input voltage range: > 2.5V MH9335 uses fixed off-time control scheme Up to 90% efficiency and 2MHz switching frequency can be achieved. Up to 2MHz switching frequency Th off-time The ff i can be b set by b an externall capacitor i and resistor. Package The LED current can be set by an exteranal resistor. Typical Application 深圳明和科技有限公司 www.led-ics.com 1／6 MH9335 Boost LED Driver IC Pin Assignment Pin No. Pin Name Descripition 1 VSS Ground 2 EN Chip Enable 3 COMP Compensation 4 FB Voltage feedback 5 DRV Driver 6 CS Current sensing 7 TOFF Off time selection 8 VDD Power supply Absolute Maximum Ratings Type Symbol Description Value Unit Voltage Vmax Maximum voltage on VDD pins i 8 V Vminmax Voltage range on EN, CS and FB pins -0.3VDD+0 .3 V Tmin-max Operation temperature range -20-85 ℃ g Tstorage Storage g temperature p range g -40-165 ℃ VESD ESD voltage for human body model 2000 V Thermal ESD 深圳明和科技有限公司 www.led-ics.com 2／6 MH9335 Boost LED Driver IC Electronic Characteristics Parameter Symbol Max Unit Power supply VDD 2.5 6.5 V CS ppin feedback voltage VCS 250 260 270 mV FB pin feedback voltage VFB 250 260 270 mV Operation current IDD 0.5 1 mA Off time (without ROFF and COFF) TOFF0 640 Standby current IDDQ EN pin high level voltage VENH EN pin low level voltage VENL DRV Rising Time TRISE DRV Falling Time TFALL 深圳明和科技有限公司 Test Condition Min Typ ns 1 2.0 uA V 0.8 V 500pF cap on DRV pin 50 ns 500pF cap on DRV pin 50 ns www.led-ics.com 3／6 Boost LED Driver IC MH9335 Detail Description MH9335 works in two states: ON State: the external switch is on until one of the comparators outputs a high level voltage, the MH9335 goes to OFF state. OFF State: the external switch remains off until a fixed off time and the outputs of the two comparators p are low, the MH9335 g goes to ON state and repeat p the ON and OFF pprocess. Fixed Off-Time The fixed off time TOFF is determined by ROFF and COFF as: If TOFF pin is left open, the typical value of TOFF is: 612ns The TOFF can be reduced by adding ROFF and be increased by adding COFF. It works like a traditional current mode PWM DC-DC DC DC converter except that the off time is fixed and the working frequency is variable due to the values of VIN and VOUT. The comparator connected to CS pin is used for current limiting and the one connected to FB is used for voltage feedback. 深圳明和科技有限公司 www.led-ics.com 4／6 Boost LED Driver IC MH9335 S tti LED C Setting Currentt The LED current is set by the external resistor RFB: ILED=260mV/RFB Compensation The output (COMP) of the transconductance error amplifier is used to compensate the regulator control loop. The system uses two poles and one zero to stabilize the loop. Where, AVEA=200V/V and GEA=30uV/A. 深圳明和科技有限公司 www.led-ics.com 5／6 MH9335 Boost LED Driver IC SOP8 Package Outline Symbol Dimensions In Millimoters Dimensions In Inches Min Max Min Max A 1.350 1.750 0.053 0.069 A1 0.100 0.250 0.004 0.010 A2 1.350 1.550 0.053 0.061 b 0.330 0.510 0.013 0.020 c 0.170 0.250 0.006 0.010 D 4.700 5.100 0.185 0.200 E 3.800 4.000 0.150 0.157 E1 5.800 6.200 0.228 0.244 e 1.270（BSC） 0.050（BSC） L 0.400 1.270 0.016 0.050 θ 0° 8° 0° 8° 深圳明和科技有限公司 www.led-ics.com 6／6