PCAL9714HNMP datasheet(30/56 Pages) NXP

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NXP Semiconductors

PCAL9714

Ultra low-voltage translating 14-bit SPI I/O expander with Agile I/O features, interrupt output, and

reset

002aag963

POR

time

VDD(P)

time

VPOR (rising VDD(P))

VPOR (falling VDD(P))

Figure 22. Power-on reset voltage (VPOR)

7.4 Device current consumption with internal pullup and pulldown resistors

The PCAL9714 integrates programmable pullup and pulldown resistors to eliminate external components when

pins are configured as inputs and pullup or pulldown resistors are required (for example, nothing is driving the

inputs to the power supply rails. Since these pullup and pulldown resistors are internal to the device itself, they

contribute to the current consumption of the device and must be considered in the overall system design.

The pullup or pulldown function is selected in registers 48h and 49h, while the resistor is connected by the

enable registers 46h and 47h. The configuration of the resistors is shown in Figure 5.

If the resistor is configured as a pullup, that is, connected to VDD, a current will flow from the VDD(P) pin through

the resistor to ground when the pin is held LOW. This current will appear as additional IDD upsetting any current

consumption measurements.

In the same manner, if the resistor is configured as a pulldown and the pin is held HIGH, current will flow from

the power supply through the pin to the VSS pin. While this current will not be measured as part of IDD, one must

be mindful of the 200 mA limiting value through VSS.

The pullup and pulldown resistors are simple resistors and the current is linear with voltage. The resistance

specification for these devices spans from 50 kΩ with a nominal 100 kΩ value. Any current flow through these

resistors is additive by the number of pins held HIGH or LOW and the current can be calculated by Ohm’s law.

See Figure 26 for a graph of supply current versus the number of pullup resistors.

PCAL9714

All information provided in this document is subject to legal disclaimers.

Product data sheet

Rev. 1.0 — 1 May 2023

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PCAL9714HNMP Datasheet(PDF) 30 Page - NXP Semiconductors