NanoBoard 3000 - Power

The NanoBoard 3000 is powered by a 5V regulated supply, the power module for which is supplied in the box. If the total power consumption of a given NanoBoard configuration – i.e. with connected expansion devices/peripheral board – exceeds 4A, then a higher current capacity power supply may be required. Such a power source must provide a regulated 5V +/-5% center positive supply. The connector is a 5.5mm diameter 2.5mm pin type DC jack.

A single power connector jack is provided. Power to the board is controlled through a power toggle switch. The board is powered when the switch is in the upward position.

5V power input connector and
toggle switch.

Protection on the main 5V power line is provided through a 5V/5W Zener diode, connected between the incoming (5V) regulated supply voltage and GND.

On-board adjustable voltage regulators are set to provide the following supplies for use by various resources on the board, including the Host Controller and User FPGA devices, as well as an attached peripheral board:

• 3.3V, 2.5V, 1.8V – using AP1084 5A LDO positive adjustable voltage regulator devices (from Diodes Incorporated).

• 1.2V – using an NCP630A 3A LDO positive adjustable voltage regulator device (from ON Semiconductor).

Both the 3.3V and 5V supply buses can also be selected to power various expansion devices that can be connected to the motherboard, via the 'User Header A' and 'User Header B' connectors.

In addition, the 5V supply is passed through low dropout (LDO) regulators (TC1017Rs) to obtain regulated 3.3V supplies for the ADC, DAC and CODEC respectively.

An array of test points is provided for checking the integrity of each of the board's power supplies, including several dedicated GND points (0V).

Location on Board

The 5V power connector (designated J19) and power toggle switch (designated SW7) are located along the top edge on the solder side of the board. Looking from the rear, they can be found next to the USB port for the PC-NanoBoard interface (J10).

Power connector and toggle switch
(as seen from the rear of the board).

The adjustable voltage regulators for supplying 1.8V, 2.5V, 3.3V and 1.2V (designated U39 - U42 respectively) are located on the solder side of the board, north of the audio jacks.

These regulators, given their PCB only heatsinking, are designed for limited current draw only. If a custom Peripheral board is to be designed that will draw significant power from the regulated supplies, then it is recommended you consider designing in a separate DC-DC converter or regulator driven directly from the 5V rail.

Adjustable voltage regulators.

The test points for the 5V (designated TP2), 3.3V (designated TP4), 2.5V (designated TP5), 1.8v (designated TP6) and 1.2V (designated TP7) supplies are located on the component side of the board, to the left of the user prototyping area. A GND test point (designated TP1) is also included in this group.

Test points for main
power supplies.

Test points for the +B power supply (the incoming power supply on the jack side of the toggle switch) and GND can also be found to the right of the prototyping area (designated TP3 and TP8 respectively).

Additional power-releated
test points.

All power supplies (and GND) are also wired through to points in the prototyping area.

Power supply test points made available to the prototyping area.

Schematic Reference

Power supply-related circuitry can be found on the following sheets of the motherboard schematics:

• Sheet 2 (PSU.SchDoc, entitled NB3000 Power Supplies) - top sheet for all power supplies on the NanoBoard 3000.

• Sheet 3 (PSU_1084_ADJ.SchDoc, entitled PSU AP1084KL ADJ) – adjustable regulator circuit used for 1.8V, 2.5V and 3.3V supplies.

• Sheet 4 (PSU_1084SET_1V8.SchDoc, entitled PSU AP1084KL Set To 1V8) – external resistors used to adjust the AP1084 voltage output to 1.8V.

• Sheet 5 (PSU_1084SET_2V5.SchDoc, entitled PSU AP1084KL Set To 2V5) – external resistors used to adjust the AP1084 voltage output to 2.5V.

• Sheet 6 (PSU_1084SET_3V3.SchDoc, entitled PSU AP1084KL Set To 3V3) – external resistors used to adjust the AP1084 voltage output to 3.3V.

• Sheet 7 (PSU_NCP630_ADJ.SchDoc, entitled PSU NCP630A ADJ) – adjustable regulator circuit used for the 1.2V supply.

• Sheet 8 (PSU_NCP630SET_1V2.SchDoc, entitled PSU NCP630A Set To 1V2) – external resistors used to adjust the NCP630A voltage output to 1.2V.

• Sheet 9 (PSU_TC1017R_3V3.SchDoc, entitled PSU TC1017R 3V3) – Low dropout (LDO) Regulator used to provide 3.3V supply for the ADC, DAC and CODEC.

• Sheet 10 (PWJACK+SWITCH.SchDoc, entitled Power Jack & Switch) – 5V power jack and toggle switch.

Further Device Information

For more information on the AP1084 device, refer to the datasheet (AP1084.pdf available at www.diodes.com.

For more information on the NCP630A device, refer to the datasheet (NCP630-D.pdf available at www.onsemi.com.

For more information on the TC1017R device, refer to the datasheet (21813d.pdf) available at www.microchip.com.