CVA6629S

Triple 180MHz CRT Driver CORPORATION CVA6629S FEATURES DESCRIPTION The CVA6629S contains three wideband amplifiers designed specifically to drive high resolution CRTs. It features excellent gray scale linearity and high load capacitance driving capability. This device can drive monitors with resolution of 1600 x 1280 (non-interlaced) with pixel frequency of 350MHz. The part is housed in 12L Ceramic package with heat sink grounded. ORDERING INFORMATION Part CVA6629S Package CY12B Temperature -20oC to +100oC • • • • • Rise/Fall Time. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5ns Swing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70VP-P Symmetrical Rise and Fall Time Excellent Gray Scale Linearity APPLICATION CRT Driver for up to 110kHz Monitors with Resolution upto 1600 x 1280 (Non-Interlaced). CONNECTION DIAGRAM AND SIMPLIFIED SCHEMATIC Q1 Q2 5.7K 1 1 2 3 4 5 6 7 8 9 10 11 GND B 12 OUT B IN R GND R OUT R V+ R GND G OUT G V+ G V+ B IN G IN B Q4 Q3 250 1j-40 CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025 CVA6629S CORPORATION ABSOLUTE MAXIMUM RATINGS Supply Voltage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85V Storage Temperature . . . . . . . . . . . . . . . . . . -25oC to +125oC Operating Temperature . . . . . . . . . . . . . . . . -20oC to +100oC Lead Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . +300oC DC ELECTRICAL CHARACTERISTICS VS = 80V, CL = 10pF, TCASE = +25oC. See Figure 1. SYMBOL ICC VIN DC VOUT DC AV CHARACTERISTICS Supply Current Input DC Level Output DC Level Voltage Gain Gain Matching 1.3 36 10 MIN TYP 37 1.5 40 12 0.2 MAX 42 1.7 44 14 UNITS mA V V V dB AC ELECTRICAL CHARACTERISTICS VS = 80V, CL = 10pF, VOUT = 50VP-P, TCASE = +25oC. See Figure 1. SYMBOL tr tf BW Le OS CHARACTERISTICS Rise Time Fall Time Bandwidth Linearity Overshoot MIN TYP 2.8 2.7 180 5 4 MAX 3.5 3.5 UNITS ns ns MHz % % FIGURE 1. TEST CIRCUIT VCC C3 C2 R2 INPUT R1 R4 C4 1,5,9 VCC 4,8,12 VOUT D1 R5 R6 L1 C6 2,6,10 1/3 CVA6629S VIN OUTPUT D2 CL C1 3,7,11 GND R1 = 15Ω R2 = 430Ω R4 = 200k R5 = 22Ω R6 = 22Ω C1 = VARIABLE 20 TO 150pF TYPICAL 68pF C2 = VARIABLE 4 to 20pF TYPICAL 17pF C3 = 75pF C4 = 10µf/160V C6 = 0.01µf/160V C L = 10pF D1 = DS464 D2 = DS464 L1 = 150nH 1Q-03 CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025 CVA6629S CORPORATION APPLICATION INFORMATION The CVA6629S is a transimpedance amplifier with two stage feedback configurations. Any change in input current will be reflected as change in output voltage swing. A resistor in series with the input will change the CVA6629S into a voltage amplifier. The output is emitter follower with load(capacitive) driven capability. With a true Class AB output stage, the rise and fall time is symmetric. CVA6627S has an internal feedback resistor of 5.7KΩ. In the absence of any input signal, the VOUT DC is set by VOUT (DC) = (1 + RF ) VIN (DC); RB = 250Ω. RB 3) Streaks and overshoot: For a cross-hatch pattern with white background, a whitish line will appear just after the black line, this is called streak. Looking at the waveform it is due to undershoot of the waveform. For a Box pattern with white background, a dark black area just after white is a sign of overshoot. It is due to overshoot of the waveform. Adjusting the value of C2, R1, C1 will get the optimum result. The value of C2 should be kept at minimum for less overshoot, typical is