27 Current Bias Generator (CBG)

Note:
  1. This data sheet summarizes the features of the dsPIC33CDVL256MC506 family of devices. It is not intended to be a comprehensive reference source. To complement the information in this data sheet, refer to “Current Bias Generator (CBG)” (www.microchip.com/DS70005253) in the “dsPIC33/PIC24 Family Reference Manual”.
  2. Some registers and associated bits described in this section may not be available on all devices. Refer to Memory Organization in this data sheet for device-specific register and bit information.

The Current Bias Generator (CBG) consists of two classes of current sources: 10 μA and 50 μA sources. The major features of each current source are:

  • 10 μA Current Sources:
    • Current sourcing only
    • Up to four independent sources
  • 50 μA Current Sources:
    • Selectable current sourcing or sinking
    • Selectable current mirroring for sourcing and sinking
Table 27-1. CBG Channel Availability
Package TypeISRCxIBIASx
64-pin0, 1, 2, 30, 1, 2, 3

A simplified block diagram of the CBG module is shown in Figure 27-1.

Figure 27-1. Constant-Current Source Module Block Diagram(2)
Note:
  1. RESD is typically 350 Ohms.
  2. The ADC analog input is shown only for clarity. Each analog peripheral connected to the pin has a separate Electrostatic Discharge (ESD) resistor.