NCP5603GEVB ON Semiconductor, NCP5603GEVB Datasheet - Page 5

• Manufacturer Part Number: NCP5603GEVB
• Description: EVAL BOARD FOR NCP5603G HI FREQ
• Manufacturer: ON Semiconductor

Specifications of NCP5603GEVB

• Design Resources: NCP5603 EVB BOM NCP5603GEVB Gerber Files NCP5603 EVB Schematic
• Current - Output / Channel: 160mA
• Outputs And Type: 1, Non-Isolated
• Voltage - Output: 4.5 ~ 5 V
• Features: Dimmable
• Voltage - Input: 3V or 3.6V
• Utilized Ic / Part: NCP5603
• Core Chip: NCP5603
• Topology: Charge Pump
• No. Of Outputs: 1
• Development Tool Type: Hardware - Eval/Demo Board
• Leaded Process Compatible: Yes
• Mcu Supported Families: NCP5603
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: NCP5603G
• Other names: NCP5603GEVBOS

assembled in a standard battery holder, the operating mode
being selected by the S1, S5 and S6 switches. Since the total
current is limited by the DC/DC converter, the backlights
LEDs are automatically deactivated when either the Torch
or the Flash are selected. Moreover, the Flash is not available
while the Torch is running.
switch S1 is associated with potentiometer P1. When the
switch is connected to ground, the NCP5603 enabling pin
EN is high and the brightness is maximized. When the
depicted Figure 4, and no uncontrolled current takes place
when the system starts up from scratch.
With a startup time well below 1 ms (from zero to full Vout,
see Figure 4), the NCP5603 is fast enough to accommodate a
flash application as shown in the demo board.
Table 2. Demo Board Efficiency
The system is powered by two AA cells in series,
An extra feature, backlight dimming, is provided by
The inrush current is internally limited by the chip, as
3.50 V
3.50 V
3.50 V
3.10 V
3.10 V
3.10 V
V
bat
Figure 4. Typical Startup Timing
132 mA
170 mA
131 mA
169 mA
300 mA
2.3 mA
I
bat
4.42 V
4.92 V
4.42 V
4.92 V
4.92 V
V
0 V
out
I
16.5 mA
21.4 mA
16.5 mA
21.4 mA
142 mA
out
0 mA
http://onsemi.com
/LED
AND8192/D
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switch S1 is flipped to the Vcc position, the RESET of U5A
is released and the EN pin is clocked High / Low by the clock
generated by U2A / U2B. Simultaneously, diode LED D7
turns ON to identify the PWM mode of operation. The duty
cycle of the U5A / Q output is manually adjusted by
potentiometer P1 to set the brightness of the four associated
LED.
temperature (see Table 2), the results being fully within the
NCP5603 data sheet specifications.
Although there is no dedicated pin, the LED brightness can
be dimmed by means of the EN digital control. The
waveform captured in Figure 5 illustrate this behavior, the
PWM being intentionally arranged out of the audio band for
a portable system.
The efficiency of the system has been evaluated at room
I
85.6 mA
85.6 mA
out
142 mA
66 mA
66 mA
0 mA
Total
Figure 5. Typical Digital Dimming
63.14%
70.78%
71.83%
80.38%
75.12%
Yield
−
Torch operation
Comments
No Load