SLVUB50C June   2017  – March 2019 UCD90120A , UCD90124A , UCD90160 , UCD90160A , UCD90240 , UCD90320 , UCD90320U , UCD9090 , UCD9090-Q1 , UCD9090A , UCD90910

 

  1.   UCD90xxx Sequencer Schematics Guidelines
    1. 1 Introduction
    2. 2 UCD Power Supply Review
      1. 2.1 UCD90240, UCD90320 and UCD90320U
      2. 2.2 Remaining UCD90xxx Devices
    3. 3 I/O Signals Review
      1. 3.1 Analog Monitor (MONx/AMONx) Pin Review
      2. 3.2 PMBUS Signals Review
      3. 3.3 GPIO Pins Review
      4. 3.4 Margin Pins Review
      5.      Trademarks
  2.   Revision History

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