MITSUBISHI(Standard Linear ICs) M62293FP 3.3V, 2.5V FIXED 2-OUTPUT VOLTAGE DC-DC CONVERTER DESCRIPTION M62293FP is 3.3V and 2.5V fixed stable 2-output step-down DC-DC converter. It is possible to simplify peripheral circuit and to design compact and low cost sets because this device includes peripheral devices in small size 8pin package. The IC also has Reset circuit with time delay that monitors power supply(Vcc=5V) and one regulator output(Vout1=3.3V;IN1 terminal), therefore an application system is protected system errors. Especially this is most suitable for application sysytem with microprocessor and ASIC. PIN CONFIGURATION(TOP VIEW) Cout1 1 8 IN1 GND 2 7 RESET Cout2 3 6 Cd Vcc 4 5 IN2 FEATURES Outline 8P2S-A ● 3.3V and 2.5V step-down converter ● 4 to 15V wide input supply voltage (Vcc=5V typ.) ● Reset circuit with time delay monitors supply voltage(Vcc=5V)and regulator output (3.3V) ● 110kHz fixed frequency oscillator without peripheral devices ● 8pin SOP package APPLICATION application system with microprocessor and ASIC BLOCK DIAGRAM Vcc Cd IN1;3.3V 25µA RESET Vref 1.25V 0.6µA comparator (3.3V detect) comparator (Vcc detect) Vcc oscillator (110kHz) Cout2 Cout1 PWM comp. op amp op amp IN1(3.3V) IN2(2.5V) ( 1 /4) PWM comp. GND 000131 MITSUBISHI(Standard Linear ICs) M62293FP 3.3V, 2.5V FIXED 2-OUTPUT VOLTAGE DC-DC CONVERTER ABSOLUTE MAXIMUM RATINGS(Ta=25C,unless otherwise noted) Symbol Vcc Io Parameter Conditions Ratings Supply voltage Output current(DC-DC converter block) ch1,ch2 Unit 16 V mA mW Pd Power dissipation Ta=25˚C 30 6 440 Kθ Topr Thermal derating Ta>25˚C 4.4 mW/˚C Operating temperature -20~+85 ˚C Tstg Storage temperature -40~+125 ˚C IoRESET Output current(Reset block) mA ELECTRICAL CHARACTERISTICS(Ta=25C,Vcc=5V,unless otherwise noted) Block All Blocks Symbol Parameter Vcc Supply voltage Icc Supply current Test condition Limits Unit Min. Typ. Max. 4.0 - 5.0 15 V 1.5 2.8 mA ch1 output 3.15 3.30 3.45 2.37 - 2.50 2.63 Without load DC-DC Converter Block Vo1 Vo2 Error Amp. Oscillator Output Output voltage V Vreg-L Line regulation ch2 output Vcc=4~12V 5 15 mV Iin Input current 1 ch1 - 150 450 µA Iin Input current 2 ch2 - 100 300 µA 65 - 110 90 160 - KHz -1 - 1.2 1 2.0 V V 3.6 30 3.8 50 4.0 80 V mV 2.46 2.58 2.70 V 30 50 80 mV µA fosc Oscillator frequency TDUTY Maximum ON duty ICL Output leakage current Vcc=12V, Vc=12V Output saturation voltage Io=10mA,Darlington connection Vs1 Detecting voltage 1 Vcc=5V detection ∆Vs1 Vs2 ∆Vs2 hysterisys voltage 1 Vsat % Reset circuit Block Reset Circuit Detecting voltage 2 ch1output(3.3V)detection Hysterisys voltage 2 IPD Cd output current tpd Delay time Cd=4700pF -1.1 5 -0.6 10 -0.3 20 msec IOC RESET output current Vcc=5V, Vo=1/2 x Vcc -40 -25 -17 µA VOL RESET LOW voltage IoRESET=4mA VOH RESET High voltage 0.8Vo1 ( 2 /4) 0.2Vo1 - V V 000131 MITSUBISHI(Standard Linear ICs) M62293FP 3.3V, 2.5V FIXED 2-OUTPUT VOLTAGE DC-DC CONVERTER RESET BLOCK timing chart 5V 3.85V 3.80V 0V t 3.3V 2.63V 2.58V 0V t Vo1 td td td 0V t td : RESET Delay Time ••• td(msec) = 2.13 × 10 × Cd(pF) -3 ( 3 / 4) 000131 MITSUBISHI(Standard Linear ICs) M62293FP 3.3V, 2.5V FIXED 2-OUTPUT VOLTAGE DC-DC CONVERTER APPLICATION CIRCUIT (3.3V and 2.5V 2-output voltage DC-DC converter VIN(5V) + Cin Vcc VOUT1(3.3V) R2 IN1 + Co1 Cout1 L1 + R4 Q2 Cout2 IN2 RESET Cd Co2 D1 R1 M62293FP VOUT2(2.5V) Q1 R3 GND L2 D2 3.3V LINE 2.5V LINE MCU etc. THE EXPRESSION OF CIRCUIT CONSTANTS Constants TON TOFF (TON+TOFF)MAX TOFF(MIN) TON(MAX) L(MIN) Ipk Expressions VO+VF VIN - VCE(sat) - VO 1 fosc fosc:110KHz(Vcc=5V) ( TON + TOFF) / ( 1+ TON ) TOFF 1 fosc - TOFF ( VIN - VCE(sat) - VO ) x TON(MAX) ∆Io Io + 1 ∆Io 2 note: • VF : Forward voltage drop of an external diode • Vsat : Output saturation voltage of an external switching transistor. • ∆IO : Set to 1/3 to 1/5 of maximum output current. • Choose an external transistor, diode and inductor with peak current rating approximately greater than "Ipk". ( 4 /4 ) 000131