R1221N RICOH electronics devices division, R1221N Datasheet
R1221N
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R1221N Summary of contents
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... OUTLINE The R1221N Series are PWM step-down DC/DC Converter controllers embedded with a voltage detector, with low supply current by CMOS process. Each step-down DC/DC converter in these ICs consists of an oscillator, a PWM control circuit, a reference voltage unit, an error amplifier, a soft-start circuit, a protection circuit, a PWM/VFM alternative circuit, a chip enable circuit, and resistors for voltage detection ...
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... GND n SELECTION GUIDE In the R1221N Series, the output voltage, the detector threshold, the oscillator frequency, the optional function, and the taping type for the ICs can be selected at the user’s request. The selection can be made by designating the part number as shown below; ...
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PIN CONFIGURATION PIN DESCRIPTION Pin No. Symbol 1 EXT 2 VD OUT GND 6 V OUT ABSOLUTE MAXIMUM RATING Symbol V V ...
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... ELECTRICAL CHARACTERISTICS lR1221N***A(C,E,G) Output Voltage : Vo, Detector Threshold : V Symbol Item V Operating Input Voltage IN V Step-down Output Voltage OUT DV / Step-down Output Voltage OUT DT Temperature Coefficient fosc Oscillator Frequency Df / Frequency Temperature OSC DT Coefficient I Supply Current1 DD1 I Standby Current stb I EXT "H" Output Current ...
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... Output Voltage : Vo, Detector Threshold : V Symbol Item V Operating Input Voltage IN V Step-down Output Voltage OUT DV / Step-down Output Voltage OUT DT Temperature Coefficient fosc Oscillator Frequency Df / Frequency Temperature OSC DT Coefficient I Supply Current1 DD1 I Standby Current stb I EXT "H" Output Current EXTH I EXT "L" Output Current ...
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TEST CIRCUITS A) PMOS + ...
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... Release Voltage from Reset condition must not be more than Output voltage of DC/DC converter. (Detector Threshold Voltage´1.07 < Output Voltage of DC/DC converter´0.98 l When the R1221NXXXX is on stand-by mode, the output voltage of VD resistor for VD pin is pulled up another power supply, a certain amount of current is loading through the OUT resistor ...
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Use capacitors with a capacity of 22mF or more for V as tantalum capacitors. We recommend you to use capacitors with an allowable voltage which is at least twice as much as setting output voltage. This is because there ...
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In Equation 1, V OUT change of the current at OFF. When the output current(IOUT) is relatively small, topen<toff as illustrated in the above diagram. In this case, the energy is charged in the inductor during the ...
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Capacitor As for C , use a capacitor with low ESR(Equivalent Series Resistance) and a capacity of at least 10mF for stable IN operation. C can reduce ripple of Output Voltage, therefore 47mF to 100mF tantalum type is recommended. ...
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... I (mA) OUT CD104-27uH Si3443DV 100 100 1000 (mA) OUT - 11 - R1221N15XH 13. 2.3V 1E-05 0.0001 0.001 0.01 I Output Current OUT R1221N33AA(VIN=12V) 0 100 I (mA) Output Current OUT R1221N33AB(VIN=12V) 0 100 I (mA) Output Current OUT 12345 L=27uH 0.1 1 (A) CD104-27uH Si3443DV 1000 CD104-27uH Si3443DV ...
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... I (mA) OUT CD104-27uH Si3443DV 100 100 1000 (mA) OUT - 12 - CD104-27uH R1221N33AC(VIN=12V) Si3443DV 1 10 100 Output Current I (mA) OUT R1221N50XA(VIN=12V) 0 100 Output Current I (mA) OUT R1221N50XB(VIN=12V 100 I (mA) Output Current OUT 1000 CD104-27uH Si3443DV 1000 CD104-27uH Si3443DV 1000 ...
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... I (mA) OUT - 13 - R1221N50XC(VIN=12V) 0 100 Output Current I (mA) OUT R1221N50XA VIN6V VIN8V VIN12V 1 10 100 I (mA) Output Current OUT L=27uH R1221N50XB C=47uF(Ta) VIN6V VIN8V VIN12V 100 Output Current I (mA) OUT ...
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... OUT L=27uH 600 500 400 300 200 100 (V) IN L=27uH 1.53 1.52 1.51 1.50 1.49 1. L=27uH R1221N50XC C=47uF(Ta) VIN6V VIN8V VIN12V 1 10 100 I (mA) Output Current OUT R1221N15XA Input Voltage V (V) IN L=27uH R1221N15XA Input Voltage V (V) IN 1000 L=27uH 15 15 ...
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... Temperature Topt 7) Detector Threshold vs. Temperature R1221N25XA(VD=2.0V) 2.01 2.00 1.99 1.98 1.97 -50 0 Temperature Topt Rev. 1.11 L=27uH 3.36 3.34 3.32 3.30 3.28 3.26 3. (V) IN L=27uH 1.51 1.50 1.49 1.48 1.47 50 100 -50 (°C) V =6V IN 1.22 1.21 1.20 1.19 1.18 50 100 (° L=27uH R1221N33AA Input Voltage V (V) IN L=27uH R1221N15XB 0 50 Temperature Topt (°C) R1221N15XB(VD=1.2V) - Temperature Topt (°C) 12345 15 100 V =6V IN 100 ...
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... IN 50 100 (°C) L=27uH V =4.5V IN 360 340 320 300 280 260 240 50 100 -50 (°C) 100 90 80 VIN15V VIN13.2V 70 VIN8V 60 50 -50 50 100 (° L=27uH R1221N25XA V =3. 100 Temperature Topt (°C) R1221N33AG VIN15V VIN13.2V VIN8V 0 50 100 Temperature Topt (°C) ...
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... Rev. 1.11 L=27uH V =4. 100 -50 (°C) V =4.5V IN 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 50 100 (°C) V =4. -50 50 100 (° L=27uH R1221N25XA V =3. Temperature Topt (°C) R1221N25XA V =3. Temperature Topt (°C) V =4.5V IN R1221N33AG 0 50 (°C) Temperature Topt 12345 100 100 100 ...
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... R1221N33AB -50 0 Temperature Topt 15) EXT ”L” Output Current vs. Temperature R1221N33AB -50 0 Temperature Topt 12345 Rev. 1.11 V =8. -50 50 100 (°C) 50 100 (°C) 50 100 (° =8.0V IN R1221N25XA 0 50 100 Temperature Topt (°C) ...
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... Temperature Topt 17) Load Transient Response R1221N33AA 3.4 3.3 3.2 3.1 3 2.9 2.8 2.7 2.6 2.5 2.4 0 0.0005 Time (sec) R1221N33AB 3.4 3.3 3.2 3.1 3 2.9 2.8 2.7 2.6 2.5 2.4 0 0.0005 Time (sec) Rev. 1.11 50 100 (°C) V =5V IN L=27uH 3.6 3.5 3.4 3.3 3.2 3.1 500 3 2.9 2.8 2.7 2.6 0.1 0 0.001 V =5V IN L=27uH 3.6 3.5 3.4 3.3 3.2 500 3.1 3 2.9 2.8 2.7 0.1 2.6 0 0.001 - =5V IN R1221N33AA L=27uH 500 0.1 0.05 0.1 Time (sec) V =5V IN R1221N33AB L=27uH 500 0.1 0.05 0.1 Time (sec) 12345 ...
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... Time (sec) 12345 Rev. 1.11 V =5V IN L=27uH 3.6 3.5 3.4 3.3 3.2 3.1 500 3 2.9 2.8 2.7 0.1 2.6 0.001 0 V =5V IN L=27uH 3.6 3.5 3.4 3.3 3.2 3.1 500 3 2.9 2.8 2.7 0.1 2.6 0 0.001 L=27uH =0mA) OUT 3.5 3 2.5 2 1.5 1 0 -1 -3.5 0.01 0.02 -0. =5V IN R1221N33AC L=27uH 0.05 Time (sec) V =5V IN R1221N33AD L=27uH 0.05 0.1 Time (sec) R1221N33AA (V =5V,I =0mA) IN OUT 0 0.01 Time (sec) 500 0.1 0.1 500 0.1 L=27uH 5 0 0.02 ...
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... OUT L=27uH 3.5 2.5 1.5 0.5 10 -0.5 -1.5 -2.5 0 -3.5 0.01 0.02 =100mA) OUT L=27uH 3.5 3 2.5 2 1 -0 -2.5 -3 -3.5 0.01 0. R1221N33AB (V =5V,I =0mA) IN OUT -0.01 0 0.01 Time (sec) R1221N33AA (V =5V,I =100mA) IN OUT -0.01 0 0.01 Time (sec) R1221N33AB (V =5V,I =100mA) IN OUT -0.01 0 0.01 Time (sec) 12345 L=27uH 5 0 0.02 L=27uH 5 0 0.02 L=27uH 5 0 0.02 ...