F280049C的DAC连接JP4的3.3V基准电压需要连接GND吗

你好，你用的硬件是TI的launchPAD吗？

是的，是LAUNCHXL-F280049C

你好，请问你是要为DAC提供外部参考电压，所以才连接JP4的3.3V？
但是launchPAD的user's guide上有说明：
2.1.8 Analog Voltage Reference Header
The analog subsystem of the F28004x allows for flexible voltage reference sources. The ADC and DAC
modules are referenced to the VREFHIx and VREFLOx pin voltages. VREFHIx can either be driven
externally or can be generated by an internal bandgap voltage reference. An external voltage can be
supplied to header J15 as an external voltage source for VREFHIx. Note that there is no signal
conditioning circuitry in place for the voltage reference. For best performance, some additional circuitry
may be required.

JP4连接VREFHIx，供电3.3V基准电压，不可以吗？我现在想问的不是DAC模块，是GND，我还有其它的模块需要JP4和JP5的电压源。