MSP432P401R_16 Datasheet, PDF (182/200 Pages) Texas Instruments – Mixed-Signal Microcontrollers

MSP432P401R, MSP432P401M
SLAS826E – MARCH 2015 – REVISED JULY 2016
www.ti.com
In addition to grounding, ripple and noise spikes on the power-supply lines that are caused by digital
switching or switching power supplies can corrupt the conversion result. A noise-free design using
separate analog and digital ground planes with a single-point connection is recommend to achieve high
accuracy.
Figure 7-3 shows the recommended decoupling circuit when an external voltage reference is used.
The reference voltage must be a stable voltage for accurate measurements. The capacitor values that are
selected in the general guidelines filter out the high- and low-frequency ripple before the reference voltage
enters the device. In this case, the 5-µF capacitor is used to buffer the reference pin and filter any low-
frequency ripple. A 50-nF bypass capacitor is used to filter out any high-frequency noise.
7.2.1.3 Layout Guidelines
Components that are shown in the partial schematic (see Figure 7-3) should be placed as close as
possible to the respective device pins. Avoid long traces, because they add additional parasitic
capacitance, inductance, and resistance on the signal.
Avoid routing analog input signals close to a high-frequency pin (for example, a high-frequency PWM),
because the high-frequency switching can be coupled into the analog signal.
If differential mode is used for the ADC14, the analog differential input signals must be routed close
together to minimize the effect of noise on the resulting signal.
182 Applications, Implementation, and Layout
Copyright © 2015–2016, Texas Instruments Incorporated
Submit Documentation Feedback
Product Folder Links: MSP432P401R MSP432P401M