2.2 Remaining UCD90xxx Devices

For supply-voltage decoupling, provide power-supply pin bypass to the device as follows:

• The TRST pin must have a 10-kΩ pulldown resistor to ground
• The RESET pin must have a 10-kΩ pullup resistor to V33D and 1-nF decoupling capacitor to ground as shown in Figure 1. The components should be placed as close to the RESET pin as possible
• 1-μF, X7R ceramic in parallel with 0.01-μF, X7R ceramic at the BPCAP pin
• 0.1-μF, X7R ceramic in parallel with 4.7-μF, X5R ceramic at the V33D pin
• 0.1-μF, X7R ceramic in parallel with 4.7-μF, X5R ceramic at the V33A pin
• 0.1-μF, X7R ceramic at pin 7 (V33DIO1 if applicable)
• Connect the V33D pin, V33DIO1 pin (if applicable), and V33DIO2 pin (if applicable), directly to the 3.3-V supply
• Connect V33A to V33D through a 4.99-Ω resistor. This resistor and V33A decoupling capacitors form a low-pass filter to reduce noise on V33A, which improves the ADC accuracy