Documentation for the different package reference circuits, including Altium Designer files, PCB layout files, and PCB production files can be downloaded from www.nordicsemi.com.

The following reference circuits for nPM2100 show the schematics and components to support different configurations in a design.

Table 1. Reference circuit configuration
Configuration 1 Configuration 2
Battery type Single alkaline AA/AAA Lithium CR2032
LDOSW Load switch LDO regulator
VSET Grounded Not connected
VOUT 1.8 V 3.0 V
CVINT 10 μF 10 μF to 22 μF

Configuration 1

The reference schematic for a configuration with a single alkaline AA/AAA battery is shown here. In this configuration VOUT is set to 1.8 V.

Figure 1. WLCSP schematic for configuration 1
SCL SDA GPIO1 SHPHLD PG/RESET VOUT VBAT J1 B a tt e r y VBAT C4 SHPHLD D4 GPIO0 C3 SDA D3 SCL D2 SYSGDEN C2 GPIO1 D1 PG/RESET C1 AVSS2 B2 LSOUT A1 VOUT A2 VINT A3 PVSS A4 AVSS1 B1 VSET B3 SW B4 U1 nPM2100-CAAA C1 10µF C5 10µF C3 2.2µF L1 2.2µH VINT SW C2 1nF C4 1nF
Figure 2. QFN schematic for configuration 1
SCL SDA GPIO1 SHPHLD PG/RESET VOUT SW VBAT J1 B a tt e r y VINT VBA T 3 SHPHLD 4 GPIO0 5 SDA 6 SCL 7 SYSGDEN 8 GPIO1 9 AVSS1 17 LSOUT 12 VOUT 13 VINT 14 VINT 15 PVSS 16 AVSS2 11 VSET 1 SW 2 PG/RESET 10 U1 nPM2100-QEAA C5 10µF C3 2.2µF C4 1nF C1 10µF L1 2.2µH C2 1nF
Table 2. Bill of material for configuration 1
Designator Value Description Package
C1, C5 10 μF Capacitor, X5R, 6 V, ±20% 0402
C2, C4 1 nF Capacitor, X5R 0201
C3 2.2 μF Capacitor, X5R, 6 V, ±20% 0402
L1 2.2 μH Inductor, Isat > 0.55 A, DCR < 300 mΩ, ±20% 0603
U1 nPM2100 nPM2100 WLCSP16 or QFN16

Configuration 2

The reference schematic for a configuration with a Lithium CR2032 battery is shown here. In this configuration VOUT is set to 3.0 V.

Figure 3. WLCSP schematic for configuration 2
SCL SDA GPIO1 SHPHLD PG/RESET VOUTLDO VOUT VBAT J1 B a tt e r y VINT VBAT C4 SHPHLD D4 GPIO0 C3 SDA D3 SCL D2 SYSGDEN C2 GPIO1 D1 PG/RESET C1 AVSS2 B2 VOUTLDO A1 VOUT A2 VINT A3 PVSS A4 AVSS1 B1 VSET B3 SW B4 U1 nPM2100-CAAA L1 2.2µH C4 2.2µF C1 10µF C6 22µF C3 2.2µF GPIO0 SW C2 1nF C5 1nF
Figure 4. QFN schematic for configuration 2

SCL SDA GPIO0 GPIO1 SHPHLD PG/RESET VOUTLDO VOUT SW VBAT J1 B a tt e r y VINT VBA T 3 SHPHLD 4 GPIO0 5 SDA 6 SCL 7 SYSGDEN 8 GPIO1 9 AVSS1/EPAD 17 VOUTLDO 12 VOUT 13 VINT 14 VINT 15 PVSS 16 AVSS2 11 VSET 1 SW 2 PG/RESET 10 U1 nPM2100-QEAA L1 2.2µH C1 10µF C2 1nF C4 2.2µF C6 22µF C3 2.2µF C5 1nF
Table 3. Bill of material for configuration 2
Designator Value Description Package
C1 10 μF Capacitor, X5R, 6 V, ±20% 0402
C2, C5 1 nF Capacitor, X5R 0201
C3, C4 2.2 μF Capacitor, X5R, 6 V, ±20% 0402
C6 22 μF Capacitor, X5R, 6 V, ±20% 0402
L1 2.2 μH Inductor, Isat > 0.55 A, DCR < 300 mΩ, ±20% 0806
U1 nPM2100 nPM2100 WLCSP16 or QFN16

PCB guidelines

A well designed PCB is necessary to achieve good performance. A poor layout can lead to loss in performance or functionality.

To ensure functionality, it is essential to follow the schematics and layout references closely.

A PCB with a minimum of two layers, including a ground plane, is recommended for optimal performance.

The DC supply voltage should be decoupled with high performance capacitors as close as possible to the supply pins. See the schematics in Reference circuits for recommended decoupling capacitor values.

Long power supply lines on the PCB should be avoided. All device grounds, VDD connections, and VDD bypass capacitors must be connected as close as possible to the device.

PCB layout example

The PCB layouts shown here are reference layouts for configuration 2.

WLCSP PCB layout

Figure 5. PCB layout, top layer


Figure 6. PCB layout, layer 2


Figure 7. PCB layout, layer 3


Figure 8. PCB layout, bottom layer


Figure 9. Component placement


QFN PCB layout

Figure 10. PCB layout, top layer


Figure 11. PCB layout, bottom layer


Figure 12. Component placement