ncp1508 ON Semiconductor, ncp1508 Datasheet
ncp1508
Available stocks
Related parts for ncp1508
ncp1508 Summary of contents
Page 1
... It also uses synchronous rectification to increase efficiency and reduce external part count. The NCP1508 optimizes efficiency in light load conditions when switched from a normal PWM mode to a “pulsed switching” mode. The device also has a built− ...
Page 2
... Selects V . This pin contains an internal pullup resistor. out Enable for Switching Regulator. This pin is Active High to enable the NCP1508. The SHD Pin has an internal pulldown resistor to force the converter off if this pin is not connected to the external circuit. Synchronization input for the PWM converter clock signal is present, the converter uses the rising edge for the turn on ...
Page 3
MAXIMUM RATINGS Rating Maximum Voltage All Pins Maximum Operating Voltage All Pins Thermal Resistance, Junction−to−Air Operating Ambient Temperature Range ESD Withstand Voltage Moisture Sensitivity Storage Temperature Range Junction Operating Temperature Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings ...
Page 4
ELECTRICAL CHARACTERISTICS (V mode –30 to 85°C for Min/Max values, unless otherwise noted. A Characteristic V Pin CC Quiescent Current of SYNC Mode out Quiescent Current of PWM Mode out ...
Page 5
ELECTRICAL CHARACTERISTICS (continued) for PWM mode –30 to 85°C for Min/Max values, unless otherwise noted. A Characteristic SYNC PWM Mode Characteristics (continued) Feedback Voltage Accuracy, V Set = 1.0 V CB0 = L, CB1 = L, I out ...
Page 6
V 1.5 V out out 60 1.3 V out 100 200 300 I (mA) out Figure 4. Efficiency vs. Output Current in PWM Mode 100 2 ...
Page 7
1.5 V out 25°C A PWM (mA) out Figure 10. Input Current Comparison 40 1.89 V out 30 1.5 ...
Page 8
1.5 V out PWM 1 25° 0 0.2 0.4 0.6 0.8 V (V) SHD Figure 16. Output Voltage vs. Shutdown Pin Voltage 1 ms/div Figure 18. ...
Page 9
Figure 22. Line Transient Response Figure 24. Output Voltage Transition Figure 23. Load Transient Response from 1. 1.8 V http://onsemi.com 9 ...
Page 10
... OFF. Switching will continue when the output voltage falls below the threshold of OVP comparator. Pulsed Mode (PM) Under light load conditions (< 30 mA), NCP1508 can be configured to enter a low current pulsed mode operation to reduce power consumption. This is accomplished by SYNC pin held LOW. The output regulation is implemented by pulse frequency modulation ...
Page 11
... Output Voltage Selection The output voltage is digitally programmed to one of four voltage levels depending on the logic state of CB0 and CB1. Therefore if the NCP1508’s load, such as a digital cellular phone’s baseband processor, supports dynamic power management, the device can lower or raise its core voltage under software control ...
Page 12
... NCP1508 in most of applications. For example, with TDK C2012X5R0J226 output capacitor, the output ripple is less than 300 mA. Design Example As a design example, assume that the NCP1508 is used in a single lithium−ion battery application. The input voltage 3 4.2 V. Output condition ...
Page 13
... RF circuits. Interference with noise Figure 26. Soldermask Top and Silkscreen Layer sensitive circuitry in the DC−DC converter can be reduced by distance between them. The following shows NCP1508 demo board layout and suggested bill of materials. Figure 25. Top and Silkscreen Layer http://onsemi.com ...
Page 14
Table 3. Bill of Materials Component Value C 10 mF, X5R, 6 mF, X5R, 6.3 V out L 6.8 mH *Output current calculated from **Calculated output current from V = 4.2 ...
Page 15
... G 0.50 BSC 0.020 BSC H 1.23 1.28 0.048 0.050 J 0.20 REF 0.008 REF K 0.00 0.05 0.000 0.002 L 0.35 0.45 0.014 0.018 M 1.50 BSC 0.059 BSC N 1.50 BSC 0.059 BSC P 0.88 0.93 0.035 0.037 R 0.60 0.80 0.024 0.031 ON Semiconductor Website: www.onsemi.com Order Literature: http://www.onsemi.com/orderlit For additional information, please contact your local Sales Representative NCP1508/D ...