SNAS461G May 2010 – November 2018 LM98640QML-SP
PRODUCTION DATA.
Refer to the PDF data sheet for device specific package drawings
The inputs to the LM98640QML-SP are typically AC coupled in Correlated Double Sampling Mode (CDS Mode) because of the switching between two signals. In Sample and Hold Mode (S/H Mode), DC coupling or AC coupling is possible depending on the signal type. The circuit of Figure 17 shows the input structure of the LM98640QML-SP. The DC bias point for the LM98640QML-SP side of the AC coupling capacitor can to be set using an external DC bias resistor network, by using the CLPIN configuration, or by using the BITCLP configuration. A typical CCD waveform is shown in Figure 18. Also shown in Figure 18 is an internal signal “CLAMP” which can be used to “gate” the CLPIN signal so that it only occurs during the “pedestal” portion of the CCD pixel waveform.