Electronic Components Datasheet Search |
|
CDK3400CTQ48Y Datasheet(PDF) 6 Page - Cadeka Microcircuits LLC. |
|
CDK3400CTQ48Y Datasheet(HTML) 6 Page - Cadeka Microcircuits LLC. |
6 / 11 page ©2008 CADEKA Microcircuits LLC www.cadeka.com 6 Data Sheet Functional Description Within the CDK3400/3401 are three identical 10-bit D/A converters, each with a current source output. External loads are required to convert the current to voltage out- puts. Data inputs RGB7-0 are overridden by the BLANK input. SYNC = H activates, sync current from IOS for sync- on-green video signals. Digital Inputs All digital inputs are TTL-compatible. Data is registered on the rising edge of the CLK signal. Following one stage of pipeline delay, the analog output changes tDO after the rising edge of CLK. Clock Input - CLK The clock input is TTL-compatible and all pixel data is registered on the rising edge of CLK. It is recommended that CLK be driven by a dedicated TTL buffer to avoid reflection induced jitter, overshoot, and undershoot. Pixel Data Inputs - R9-0, B9-0, G9-0 TTL-compatible Red, Green and Blue Data Inputs are reg- istered on the rising edge of CLK. SYNC and BLANK SYNC and BLANK inputs control the output level (Figure 2 and Table 1, on the previous page) of the D/A converters during CRT retrace intervals. BLANK forces the D/A outputs to the blanking level while SYNC = L turns off a current source that is connected to the green D/A converter. SYNC = H adds a 40 IRE sync pulse to the green output, SYNC = L sets the green output to 0.0V during the sync tip. SYNC and BLANK are registered on the rising edge of CLK. Data: 660mV max. Pedestal: 54mV Sync: 286mV Figure 2. Normal Output Levels BLANK gates the D/A inputs and sets the pedestal voltage. If BLANK = HIGH, the D/A inputs are added to a pedestal which offsets the current output. If BLANK = Low, data inputs and the pedestal are disabled. Sync Pulse Input - SYNC Bringing SYNC LOW, turns off a 40 IRE (7.62mA) current source which forms a sync pulse on the Green D/A con- verter output. SYNC is registered on the rising edge of CLK with the same pipeline latency as BLANK and pixel data. SYNC does not override any other data and should be used only during the blanking interval. Since this is a single-supply D/A and all signals are posi- tive-going, sync is added to the bottom of the Green D/A range. So turning SYNC OFF means turning the current source ON. When a sync pulse is desired, the current source is turned OFF. If the system does not require sync pulses from the Green D/A converter, SYNC should con- nected to GND. Blanking Input - BLANK When BLANK is LOW, pixel inputs are ignored and the D/A converter outputs fall to the blanking level. BLANK is registered on the rising edge of CLK and has the same pipeline latency as SYNC. D/A Outputs Each D/A output is a current source. To obtain a voltage output, a resistor must be connected to ground. Output voltage depends upon this external resistor, the reference voltage, and the value of the gain-setting resistor con- nected between RREF and GND. Normally, a source termination resistor of 75Ω is connect- ed between the D/A current output pin and GND near the D/A converter. A 75Ω line may then be connected with an- other 75Ω termination resistor at the far end of the cable. This “double termination” presents the D/A converter with a net resistive load of 37.5Ω. The CDK3400/3401 may also be operated with a single 75Ω terminating resistor. To lower the output voltage swing to the desired range, the nominal value of the resistor on RREF should be doubled. R, G, and B Current Outputs - IOR, IOG, IOB The R, G, and B current source outputs of the D/A converters are capable of driving RS-343A/SMPTE-170M compatible levels into doubly-terminated 75Ω lines. Sync pulses may be added to the Green D/A output. |
Similar Part No. - CDK3400CTQ48Y |
|
Similar Description - CDK3400CTQ48Y |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |