R1218X Ricoh Corporation, R1218X Datasheet
R1218X
Related parts for R1218X
R1218X Summary of contents
Page 1
... The R1218X can drive white LEDs with high efficiency with low supply current. A diode is built-in the R1218XXX1A, therefore it is possible to drive up to 4LEDs without an external diode. The R1218XXX2A, an external diode is necessary, however serial LEDs can be driven with the R1218XXX2A ...
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... BLOCK DIAGRAMS R1218XXX1A Err. Amp PWM Comp + + – – ref ref ref ref Shu tdown delay R1218XXX2A Err. Amp PWM Comp + + – – Vref Vref Vref Vref Shutdown delay 2 4 DataSheet U ...
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... Feedback Pin FB Descriptions PLP1820 GND GND GND GND OUT OUT OUT OUT Pin Description R1218X 3 ...
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... Chip Enable Pin V Feedback Pin FB Lx Switching Pin (Open Drain Output) GND Ground Pin V Power Supply Input Pin IN V Output Voltage OUT Item R1218XXX1A R1218XXX2A R1218XXX1A R1218XXX2A R1218NXXXA suspended in air R1218KXXXA*Note1 Conditions V =5.5V, V =0V load =5.5V falling IN V ...
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... R1218XXX2A V =3. =3.6V OUT V =3.6V OUT R1218X021A R1218X031A V =3.6V IN R1218X041A V rising OUT R1218X052A R1218X062A R1218X021A R1218X031A V =3.6V IN R1218X041A V falling OUT R1218X052A R1218X062A Item Conditions I =100mA DIODE V =20V, V OUT LX UVLO Detector Threshold/ UVLO Released Voltage MIN. ...
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... PWM signal and resisters, R1, R2, R3, and R4 in the figure5.Duty 6 4 DataSheet U .com OVP Detector Threshold, OVP Released Voltage Test Circuit GND GND GND GND R1218X062A L1 22uH C1 1uF 0.22uF GND GND GND GND R1 10 pin ...
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... Set 0. more capacitor between V 4 DataSheet U .com Figure 4. Dimming control by DC voltage +0 )/( OUT IN OUT =3.6V, recommendation value of the inductor is 10uH or more. IN and the GND like the figure above. OUT OSC R1218X or 7 ...
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... V =1.8V IN 100 (mA) LED V =4. (mA) LED V =2.7V IN 100 (mA) LED V =3.6V R1218X021A LED Current I (mA) LED V =3.6V R1218X031A LED Current I (mA) LED ...
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... LED Current I 4 DataSheet U .com V =4. (mA) LED V =2.7V IN R1218X041A (mA) LED V =4. (mA) LED R1218X041A 100 LED Current I (mA) LED R1218X V =3. ...
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... LED V =4.2V IN L： ： ： ： LQH32CN220 Diode： ： ： ： CRS02 25℃ (mA) LED V =3.6V, R1=10Ω IN Topt=25 ℃ 5kHz 1kHz 200Hz 100 DUTY (%) R1218X062A 100 LED Current I (mA) LED V =3. ...
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... Time (ms) V =3.6V, R1=10Ω IN R1218X041A 5kHz 1kHz 200Hz 100 DUTY (%) Fosc=200Hz 2.4 3.2 4 Time (ms) Fosc=5kHz R1218X021A 25 CE Input Voltage 20 15 Output Voltage 0.04 0.08 0.12 0.16 Time (ms) Fosc=5kH R1218X041A 50 CE Input Voltage Output Voltage 0.04 0.08 0.12 0.16 Time (ms) R1218X 0 0.2 11 ...
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... DataSheet U .com VIN=3.6V,R1=10Ω 5kHz 1kHz 200Hz 60 80 100 DUTY (%) Fosc=200Hz 2.4 3 UVLO Detector Threshold/Released Voltage vs. Temperature V =3. 100 Fosc=5kHz R1218X062A 50 CE Input Voltage Output Voltage 0.04 0.08 0.12 0.16 Time (ms) R1218x041A 1.7 1.66 UVLO Released 1.62 1.58 UVLO Detector 1.54 1.5 -50 - Temperature Topt ( C) ...
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... Vin=3.6V OVP Detector Threshold OVP Released Voltage 100 Vin=3. 100 R1218x041A -50 - Temperature Topt ( C) R1218x041A Vin=3.6V 360 320 280 240 200 160 120 -50 - Temperature Topt ( C) R1218X Vin=3.6V 75 100 75 100 13 ...
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... OVP Transient Response (Topt=25 C) R1218X021A 15 12.5 OVP Voltage 10 7 R1218X062A 35 OVP Voltage 16. Efficiency dependence on inductors R1218X041A [Internal D iode Type LED Current DataSheet U .com 100 Time (ms) 60 ...