NXP Semiconductors

UM12262

FRDM-IMX91 Board User Manual

• Section "Clocks"

• Section "I2C interface"

• Section "Boot mode and boot device configuration"

• Section "PDM interface"

• Section "LPDDR4 DRAM memory"

• Section "SD card interface"

• Section "eMMC memory"

• Section "M.2 interface"

• Section "CAN interface"

• Section "USB interface"

• Section "Ethernet"

• Section "EXPI connector"

• Section "Debug interface"

• Section "Board errata"

2.1 Processor

The i.MX 91 applications processor includes single Arm Cortex-A55 processors with speeds up to 1.4 GHz.

Robust control networks are possible via the CAN-FD interface. Also, dual 1 Gbit/s Ethernet controllers, one

supporting time sensitive networking (TSN), drive gateway applications with low latency.

The i.MX 91 is useful for applications such as:

• Smart home

• Building control

• Contactless HMI

• Commercial

• Healthcare

• Industrial

Each processor provides a 16-bit LPDDR4 memory interface and other interfaces for connecting peripherals,

such as WLAN, Bluetooth, USB2.0, uSDHC, Ethernet, CAN, and multisensors.

For more detailed information about the processor, see the i.MX 91 data sheet and i.MX 91 Applications

Processor Reference Manual at https://www.nxp.com/imx91.

2.2 Power supply

The primary power supply to the FRDM-IMX91 board is VBUS_IN (12 V - 20 V) through USB Type-C PD

connector (P1).

Three DC buck switching regulators are used:

• MP8759GD (U702) switches VBUS_IN supply to SYS_5V (5 V) power supply, which is input power supply for

PCA9451AHNY PMIC (U701) and other devices on board.

• MP2147GD (U726) switches VDD_5V supply to VPCIe_3V3 (3.3 V / 4 A) for M.2 / NGFF module (P8).

• MP1605C (U730) switches VPCIe_3V3 supply to VEXT_1V8 (3.3 V / 500 mA) for onboard tri-radio module

MAYA-W476-00B (U731).

Figure 6 shows the FRDM-IMX91 power supply block diagram.

UM12262

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User manual

Rev. 3.0 — 22 April 2025

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