NCP5005 ON Semiconductor, NCP5005 Datasheet
NCP5005
Available stocks
Related parts for NCP5005
NCP5005 Summary of contents
Page 1
... NCP5005 Compact Backlight LED Boost Driver The NCP5005 is a high efficiency boost converter operating in current loop, based on a PFM mode, to drive White LED. The current mode regulation allows a uniform brightness of the LEDs. The chip has been optimized for small ceramic capacitors, capable to supply ...
Page 2
... FB NCP5005 R1 D6 GND 15 W LWT67C Figure 1. Typical Application Thermal Shutdown 4 EN 100 k GND − 300 k +200 mV Band Gap Figure 2. Block Diagram http://onsemi.com NCP5005 V bat bat 4 out MBR0530 LWT67C LWT67C LWT67C LWT67C Current Sense ...
Page 3
... Care must be observed to avoid EMI through the PCB copper tracks connected to this pin. This pin is the system ground for the NCP5005 and carries both the power and the analog signals. High quality ground must be provided to avoid spikes and/or uncontrolled operation. Care must be observed to avoid high− ...
Page 4
... ESR < 1 3.60 V bat Stand By Current mA out Stand By Current mA out = 3 mH, 3xLED, Inductor Discharging Time @ V bat out Thermal Shutdown Protection Thermal Shutdown Protection Hysteresis NCP5005 Symbol V bat V out EN V ESD qJA ...
Page 5
... Internal Switch ON Resistor @ Tamb = +25°C 5. The overall tolerance depends upon the accuracy of the external resistor. ESD PROTECTION The NCP5005 includes silicon devices to protect the pins against the ESD spikes voltages. To cope with the different ESD voltages developed in the applications, the built−in structures have been designed to handle " ...
Page 6
... Rearranging Equation 5 yields: (eq. 2) Let bat (eq. 3) Finally, the operating frequency is: The output power supplied by the NCP5005 is limited to (eq. 4) one watt: Figure 5 shows the maximum power that can be delivered by the chip as a function of the output voltage. http://onsemi.com 6 ...
Page 7
... V (V) bat Figure 5. Maximum Output Power as a Function of the Battery Supply Voltage 120 100 2.5 Figure 7. Maximum Output Current as a Function of V NCP5005 400 350 4 LED 300 250 200 = 2.0 W sense 150 Test conditions mH, R Figure 6. Typical Inductor Peak Current as a ...
Page 8
... The typical application schematic diagram is provided in Figure (eq bat bat GND GND out 3 FB NCP5005 LWT67C LWT67C LWT67C LWT67C LWT67C Figure 9. Basic Schematic Diagram http://onsemi.com GND C1 4.7 mF GND ...
Page 9
... Output Load Drive In order to optimize the built−in Boost capabilities, one shall operate the NCP5005 in the continuous output current mode. Such a mode is achieved by using and external reservoir capacitor (see Table 1) across the LED. At this point, the peak current flowing into the LED diodes shall be within the maximum ratings specified for these devices ...
Page 10
... Figure 16. Feedback Voltage Variation Frequency = f mA−L bat out 2.5 2 LED 2.0 1.5 3 LED 4 LED 1.0 5 LED 0.5 0 2.5 3.0 3.5 4.0 4.5 V (V) bat Figure 18. Typical Operating Frequency NCP5005 = 22 mH Feedback Variation vs. Temperature out 205 204 203 202 201 200 199 198 197 196 195 −40 −20 5.00 5.50 = 1.0 mF, out Figure 15. Feedback Voltage Stability 1.4 1.2 1.0 ...
Page 11
... NCP5005 TYPICAL OPERATING WAVEFORMS = 22 mH, 5 LED, I Conditions 3 bat out Figure 20. Typical Power Up Response V load Inductor Current = 22 mH, 5 LED, I Conditions 3 bat out Figure 21. Typical Start−Up Inductor Current and Output Voltage http://onsemi.com 11 V out Inductor Current = 15 mA out = 15 mA ...
Page 12
... NCP5005 TYPICAL OPERATING WAVEFORMS = 22 mH, 5 LED, I Conditions 3 bat out Figure 22. Typical Inductor Current = 22 mH, 5 LED, I Conditions 3 bat out Figure 23. Typical Output Load Voltage Ripple http://onsemi.com 12 Inductor Current = 15 mA out V Ripple load 50 mV/div Inductor Current = 15 mA out ...
Page 13
... TYPICAL OPERATING WAVEFORMS Test Conditions mH mA, V out Figure 24. Typical Output Peak Voltage 92.00 90.00 ESR = 0.3 W 88.00 86.00 84.00 ESR = 1.3 W 82.00 80.00 78.00 3 3.5 4 4.5 V (V) bat NCP5005: Efficiency = f(ESR LED, ILed = 20 mA Figure 25. Efficiency as a Function of V http://onsemi.com 13 Output Voltage Inductor Current = 3.6 V, Ambient Temperature bat 5 5.5 and Inductor ESR bat ...
Page 14
... Figure 26. Noise Returned to the Battery Test Conditions 3 bat Figure 27. Relative EMI Over 100 kHz − 30 MHz Bandwidth NCP5005 10 100 FREQUENCY (MHz mA, string of 3 LED (OSRAM LWT67C) out http://onsemi.com 14 1000 ...
Page 15
... GND 1 V out 3 FB MBR0530 NCP5005 LWT67C LWT67C LWT67C LWT67C LWT67C start and stop the converter, yielding high transients . These transients might generate spikes difficult to filter out in the rest of the application, a situation not recommended. The output current depends upon the duty cycle of the signal presented to the node Pin 3: this is very similar to the digital control discussed in Figure 31 ...
Page 16
... bat 2 GND GND V out NCP5005 C3 R4 100 nF 5 GND 10 W LWT67C LWT67C LWT67C LWT67C LWT67C Sense Resistor value, preferably well below 1.0 MW. Consequently, let R2 = 150 and the other hand, the feedback delay to control the luminosity of the LED shall be acceptable by the user less being a good compromise ...
Page 17
... V bat bat GND GND 1 V out 3 FB NCP5005 LWT67C LWT67C LWT67C LWT67C LWT67C been carried out at room temperature with mH, five LEDs in series, RFB = 22 W. http://onsemi.com 17 C1 4.7 mF GND D1 V load MBR0530 C2 1 ...
Page 18
... NCP5005 Figure 33. Operation @ PWM = 10 kHz 25% Figure 34. Magnified View of Operation @ PWM = 10 kHz 25% http://onsemi.com 18 PWM V load VFB PWR CLK PWM V load PWR CLK ...
Page 19
... Figure 35. Output Current as a Function of the Operating Condition Table 1. Recommended Passive Parts Part Manufacturer Ceramic Capacitor 1.0 mF/16 V Ceramic Capacitor 1.0 mF/25 V Ceramic Capacitor 4.7 mF/6.3 V Inductor 22 mH Inductor 22 mH Inductor 22 mH Inductor 22 mH NCP5005 NCP5005 I = f(PWM kHz out Digital EN Analog PWM 100 DC (%) Description MURATA GRM42 − ...
Page 20
... LED Sense R1 3.9 W Resistor GND Test conditions 3.6 V bat = out = 1 out Figure 36. Examples of Possible LED Arrangements NCP5005 under realistic battery supply, powering ten LED can be achieved by a series/parallel combination as depicted in Figure 36 Load D5 D1 LED LED D6 LED D2 LED D7 LED ...
Page 21
... ENABLE GND TP2 FB R1 51R Z1 GND GND Note: Use Jumper JP2 to JP3 to adjust the number of LED in the operating string Figure 37. NCP5005 Demo Board Schematic Diagram Figure 38. NCP5005 Demo Board Top Silkscreen NCP5005 V bat C1 1 mF/10 V JP1 Isense bat ...
Page 22
... Figure 33: Operation @ PWM = 10 kHz 25% Figure 34: Magnified View of Operation @ PWM = 10 kHz 25% Figure 35: Output Current as a Function of the Operating Conditions Figure 36: Examples of Possible LED Arrangements Figure 37: NCP5005 Demo Board Schematic Diagram Figure 38: NCP5005 Demo Board Top Silkscreen NOTE CAPTIONS INDEX Note 1: ...
Page 23
... D 0.25 0.50 0.0098 0.0197 G 0.85 1.05 0.0335 0.0413 H 0.013 0.100 0.0005 0.0040 J 0.10 0.26 0.0040 0.0102 K 0.20 0.60 0.0079 0.0236 L 1.25 1.55 0.0493 0.0610 2.50 3.00 0.0985 0.1181 mm inches ON Semiconductor Website: http://onsemi.com Order Literature: http://www.onsemi.com/litorder For additional information, please contact your local Sales Representative. NCP5005/D ...