CYT2606L PFM Step-Up DC-DC Converter General Description The CYT2606L Series are PFM step-up DC-DC converters with very low ripple noise due to the high operation frequency. The maximum operation frequency is 400KHz. Only three components are required to realize the conversion from the battery voltage to a selected output voltage. A driver pin (EXT) is provided for driving external power transistor to extend the output current capability where large current is required. Enable pin (EN) is also provided so that the circuit can be powered down. Ordering Information Features 400KHz Maximum Operation Frequency 2.0V to 5.0V Output Voltage With 0.1V Step Low Start-up Voltage: 0.8V at 1mA ±2% Output Voltage Accuracy Up to 88% Efficiency Output current: 300mA at 2.5V input, 3.3V output Low Ripple and Low Noise Output Current Extendable by External Switch Applications Power source for applications where a higher voltage than the battery voltage is required One to three cell battery devices Power source for cameras, camcorders, VCRs, PDAs, pagers and hand held communication instrument Typical Applications 1 of 1 CYT2606L Block Diagram + LX EXT EN Current limiting comparator buffer VOUT Error Amplifier + - PFM control 1.24V OSC 400KHz Chip Enable bandgap GND Pin Assignment Pin Name Part Marking and Package Type CYT2606L CYT2606L CYT2606L CYT2606L CYT2606L CYT2606L Description LXXT LXXF LXXE EXXT EXXF EXXE SOT-23-3 SOT-23-5 SOT-89 SOT-23-3 SOT-23-5 SOT-89 LX 2 5 3 - - - Switching pin EXT - - - 2 5 3 Buffer output for external transistor VOUT 3 2 2 3 2 2 Output voltage EN - 1 - - 1 - Chip enable (active high) GND 1 4 1 1 4 1 Ground NC - 3 - - 3 - No connection 2 of 2 CYT2606L Absolute Maximum Ratings Type Symbol Description Value Unit Voltage Vmax Maximum voltage on VOUT and VLX pins 8 V Vmin-max Voltage range on EXT and EN pins -0.3-VOUT+0.3 V ILXmax Maximum current on LX pin 1000 mA IEXTmax Maximum current on EXT pin 100 mA Psot-23-3 Maximum Power dissipation for SOT-23-3 package 0.25 W Psot-23-5 Maximum Power dissipation for SOT-23-5 package 0.25 W Psot-89 Maximum Power dissipation for SOT-89 package 0.5 W Tmin-max Operation temperature range -20-85 o C Tstorage Storage temperature range -40-165 o C VESD ESD voltage for human body mode 2000 V Current Power dissipation Thermal ESD Electronic Characteristics Parameter Symbol Output voltage accuracy △VOUT Maximum input voltage VINMAX Start-up voltage VSTART ILOAD=1mA, VIN:0→2V Hold-on voltage VHOLD ILOAD=1mA, VIN:2→0V Maximum oscillation frequency FMAX 350 400 450 KHz Oscillator duty cycle DCOSC 75 80 85 % Efficiency η 85 88 % Current limit ILIMIT 800 1000 mA Input current at no load IIN0 Input standby current EN “High” voltage level IINQ Test Condition Min Typ Max Unit -2 2 % 0.7 VOUT V 0.85 V 0.6 600 V VIN=1.8V VOUT=3.0V 20 uA VIN=1.8V VOUT=5.0V 25 uA No load, EN=“low” 1 uA V 0.4*VOUT EN “low” level 0.2 V EN “high” input current 0.1 uA EN “low” input current -0.1 EXT output current -5 uA 5 mA 3 of 3 CYT2606L Typical Characteristics (Using Internal Switch Transistor) Start-up/Hold-on Voltage(V) Start-up/Hold-on vs. Output Current 3 2.5 2 1.5 Start-up 1 0.5 L=47uH C=47uF Hold-on 0 1 10 100 1000 Output Current(mA) Output Voltage vs. Output Current 4 Output Voltage (V) 3.5 3V 2V 2.5V 3 1.5V 2.5 1V L=47uH C=47uF VOUT=3.4 V 2 1.5 0 50 100 150 200 250 300 350 Output Current (mA) 4 of 4 CYT2606L Efficiency(%) Efficiency vs. Output Current 90 88 86 84 82 80 78 76 74 72 3V 2.5V 2V 1V 1 1.5V 10 L=47uH C=47uF VOUT=3.4V 100 1000 Output Current(mA) Output Current vs. Ripple Voltage Ripple Voltage(mV) 250 200 3V 150 2.5V 2V 100 50 L=47uH C=47uF VOUT=3.4V 1.5V 1V 0 0 50 100 150 200 250 300 350 Output Current (mA) 5 of 5 CYT2606L Output Current vs. Ripple Voltage Ripple Voltage (mV) 80 70 2V 60 3V 50 2.5V 1.5V 40 1V 30 20 L=47uH C=2*47uF VOUT=3.4V 10 0 0 50 100 150 200 250 300 350 Output Current (mA) Output Current vs. Ripple Voltage 70 Ripple Voltage(mV) 60 50 2V 3V 40 2.5V 30 20 10 L=47uH C=3*47uF VOUT=3.4V 1.5V 1V 0 0 50 100 150 200 250 300 350 Output Current (mA) 6 of 6 CYT2606L Package Information Symbol A A1 A2 B c D E E1 e e1 L L1 ? Dimensions In Millimeters Min Max 1.050 1.250 0.000 0.100 1.050 1.150 0.300 0.400 0.100 0.200 2.820 3.020 1.500 1.700 2.650 2.950 0.950TYP 1.800 2.000 0.700REF 0.300 0.600 0ٛ8 ٛ0ٛ Dimensions In Inches Min Max 0.041 0.049 0.000 0.004 0.041 0.045 0.012 0.016 0.004 0.008 0.111 0.119 0.059 0.067 0.104 0.116 0.037TYP 0.071 0.079 0.028REF 0.012 0.024 8ٛ 7 of 7 CYT2606 L Symbol A b b1 c D D1 E E1 e e1 L Min 1.400 0.320 0.400 0.350 4.400 Max 1.600 0.520 0.580 0.440 4.600 Min 0.055 0.013 0.016 0.014 0.173 2.600 4.250 0.091 0.155 1.550 REF 2.300 3.940 0.061 REF 1.500 TYP 3.000 TYP 0.900 Max 0.063 0.197 0.023 0.017 0.181 0.102 0.167 0.060TYP 0.118TYP 1.200 0.035 0.047 8 of 8