ViewSonic VP2330WB Service Manual - Page 29

d) Panel interface (Pin B1,B2,C1,C2,D1,D2,A6,B6,A8,B8,A9,B9,A10,B10,) : The Gm1601H driver interface is highly programmable. 6.1.2 Power Regulator AIC1577 (U23), AP1084 (U16,U20),LT1117(U18): The AIC1577 is a current switching regulator control IC containing the primary functions required for DC to DC converters and external NMOS STEP-DOWN PWM controller ,operating input voltaqge from 4.5V to 24V The desired output voltage is determined by the equation, Volt = 0.8[ ( R218+R219) / R218]. In this case, the output voltage is 5 Volts. The AIC1577 is a low dropout operation 6.1.3 Power Regulator AP1084 (U16,U20): The AP1084 is a low dropout positive adjustable or fixed mode regulator with minimum of 5A output current capability. Specifically designed to provide supply for low voltage IC and low current 3.3V logic supply. AP1084 is guaranteed to have lower than 1.4V dropout at full load current ,provide well-regulated output of 1.25 to 3.3 with 4.7 to 12V input supply. 6.1.4 Power Regulator LT1117(U18): The LT1117 is a low drop voltage regulator ,provide up to 800 mA of output current. Concerning fixed version, are offered the output voltage:1.2V,1.8V,2.5V,2.85V,3.0V,3.3V,the regulator to reach a very tight output voltage tolerance, within ± 1% at 25°C. The adjustable LD1117 is pin to pin compatible with the other LD1117. 6.3 Power (Inverter) Board This is a specific power (inverter) board for VP2030B monitor with output of 56W /12V / 2.4A and 20V/1.8A. It provides 20 VDC to drive the four cold cathode fluorescence tubes in the backlight. 6.3.1 The inverter's electrical specification is described below. Input Output Rated Input Voltage Input Voltage Range Input Current On / Off control Voltage Rated Output Strike-on Voltage Rated Output Voltage Rate Output Frequency Rated Output Current 20Vdc 19 ~ 21 Vdc 1.8A(MAX) 2.5~5.25 for on , 0~1 for off 1800Vrms 700~900Vrms 35~80KHz 5.5~8.0 mA ViewSonic Corporation Confidential - Do Not Copy 26 VP2330wb