3 New and inherited anomalies

The following anomalies are present in revision Revision 2 of the nRF21540 chip.

ID

Module

Description

New in

Revision 2

Inherited

from

Engineering

C

7

RF

Current leakage via MODE pin affecting RF performance

X

10

System

Increased current consumption in Power-down state with

MODE pin high

X

12

SPI

Spike on MISO pin

X

13

System

Increased supply current in Power-down state with digital

input pins at high level

X

14

System

Increased supply current in Power-down state

X

Table 1: New and inherited anomalies

3.1 [7] RF: Current leakage via MODE pin affecting RF

performance

This anomaly applies to IC Rev. Revision 2, build codes QDAA-G00.

It was inherited from the previous IC revision Engineering C.

Symptoms

Current leakage via MODE pin. Both TX and RX gain, as well as LNA noise figure (NF), are affected.

Conditions

Using pin control with MODE pin pulled to VDD.

Consequences

Increased current leakage into MODE pin when pulled to VDD. TX and RX gain will be affected, as well as

the device current consumption. Higher noise figure will impact the RX sensitivity.

Workaround

Use one of the following:

1. 33 kΩ resistor in series on MODE pin.

2. SPI control and keep MODE pin pulled to GND.

4446_224 v1.2

5