MAX1610 Datasheet, PDF (11/20 Pages) Maxim Integrated Products – Digitally Controlled CCFL Backlight Power Supplies

Digitally Controlled CCFL Backlight
Power Supplies
FIGURE 4 CIRCUIT, C2 = 15pF, I_R1 = 462mA,
CCFL VL = 500V_RMS
BATT = 10V, I_BATT = 0.20A,
MINDAC = 0.5V, D/A VALUE = 11111
6V
T1
CENTER-TAP
VOLTAGE
0V
1A
C1
CURRENT
-1A
5µs/div
Figure 5. Royer Oscillator Typical Operating Waveforms for
Circuit of Figure 4
REF / 8 = 250mV
FULL-SCALE
3V
FIGURE 4 CIRCUIT, C2 = 15pF,
R1 = 545Ω,
CCFL VL = 500V_RMS, BATT = 15V,
MINDAC = 0.5V, D/A VALUE = 10000
SS
VOLTAGE
0V
6V
T1
CENTER-TAP
VOLTAGE
0V
10ms/div
Figure 6. Start-Up Waveforms for Circuit of Figure 4
MID-SCALE
MIN-SCALE = MINDAC / 8
OmV
DAC CODE
NOTE: DAC CODE 00000 FORCES THE BATT-TO-LX SWITCH OFF REGARDLESS OF CSAV OR MINDAC VOLTAGE.
Figure 7. CSAV Regulation Voltage Range
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