Schematic design

The schematic design should start by focusing on nRF9151's most critical interfaces, which are the power supplies and the radio frequency interfaces which are ANT, GPS, and AUX.

Universal Integrated Circuit Card (UICC) and control interfaces should also be designed carefully, as some of them can require components for Electrostatic Discharge (ESD) protection or noise filtering. The following figure shows the nRF9151 schematic with recommended components.

Figure 1. nRF9151 application schematic drawing

The following table provides information on recommended components.

Table 1. nRF9151 application component recommendations
Designator	Recommended value	Description	Footprint	Example part number
C1, C2	1 µF	Capacitor, X5R, ±20%, 10 V	0201	GRM033R61A105ME15
C3	47 µF	Capacitor, X5R, ±20%, 10 V	0805	GRM21BR61A476ME15
C4	10 µF	Capacitor, X5R, ±20%, 10 V	0603	GRM188R61A106MAAL
C5, C8	0.1 µF	Capacitor, X5R, ±20%, 6.3 V	0201	GRM033R60J104ME19
C6, C7	4.7 µF	Capacitor, X5R, ±20%, 6.3 V	0402	GRM155R60J475ME47
FB1	22 Ω	Ferrite Bead, 22 Ω at 100 MHz, 6 A, 8 mΩ	0603	BLM18SD220SN1
R1	10 kΩ	Resistor, ±5%, 0.05 W	0201	RC0201JR-0710KL
R2	1 kΩ	Resistor, ±5%, 0.05 W	0201	RC0201JR-071KL

When selecting the components, consider the following factors.

Capacitors (all types): Higher temperature grade capacitors, such as the X6S series, are recommended if the product operates mainly in high temperature conditions above 65°C.
VDD capacitors: Lower voltage rating capacitors can be considered for products with a VDD voltage that is typically much lower than 5.5 V.
Capacitors C3 and C4: Smaller package size and capacitance value components can be used as long as the VDD voltage is ≥3.0 V under load. Current consumption peaks during TX.; The total capacitance in the VDD supply node affects current peaks, EMI, and voltage ripple at the VDD line. This can affect the end product's radiated performance.
Ferrite bead FB1: A smaller package size component can be used if the EMI performance and VDD voltage are at an acceptable level in the end product.; Use close to equal DC resistance and frequency characteristics as in the selected component.

For recommended antenna matching component values and topology, see the Long-Term Evolution (LTE) and Global Navigation Satellite System (GNSS) antenna datasheets. For more information on the antenna design and interface, see nRF91 Series Antenna and RF Interface Guidelines.