ZYBO™ FPGA Board Reference Manual
Copyright Digilent, Inc. All rights reserved.
Other product and company names mentioned may be trademarks of their respective owners.
Page
4
of
26
1
Power Supplies
The ZYBO can be powered from the Digilent USB-JTAG-UART port (J11), or from an external power supply. Jumper
JP7 (near the power switch) determines which power source is used. There are three valid configurations for this
jumper corresponding to the three powering options: USB, wall wart with barrel jack, and battery pack. There is a
diagram on the board silkscreen indicating all three.
All on-board power supplies are enabled or disabled by the power switch SW4. The power indicator LED (LD11) is
on when all the supply rails reach their nominal voltage. An overview of the power circuit is shown in Fig.2
Figure 2. Power circuit overview.
A USB 2.0 port can deliver maximum 0.5A of current according to the specifications. This should provide enough
power for lower complexity designs. An idling blank board consumes around 0.2A from the 5V input supply. As an
example, the standalone lwIP echo server sample project replying to ping requests consumes 0.38A on average.
More demanding applications, including any that drive multiple peripheral boards or other USB devices, might
require more power than the USB port can provide. In this case, power consumption will increase until it’s limited
by the USB host. This limit varies a lot between manufacturers and depends on many factors. When in current
limit, once the voltage rails dip below their nominal value, the Zynq is reset by the Power-on Reset signal and
power consumption returns to its idle value. Also, some applications may need to run without being connected to
a PC’s USB port. In these instances an external power supply or battery pack can be used.
An external power supply (wall wart) can be used by plugging into to the power jack (J15) and setting jumper JP7
to "wall". The supply must use a coax, center-positive 2.1mm internal-diameter plug, and deliver 4.5VDC to
5.5VDC and at least 2.5A of current (i.e., at least 12.5W of power). Suitable supplies can be purchased from the
Digilent website or through catalog vendors like DigiKey. Power supply voltages above 6VDC might cause
permanent damage.
An external battery pack can be used by connecting the battery’s positive terminal to the center pin of JP7 and the
negative terminal to the pin labeled J14 next to JP7. The external battery pack must be limited to 5.5VDC. The
minimum voltage of the battery pack depends on the application: if the USB Host (J10) or HDMI Source (J8)
function is used, at least 4.6V need to be provided. In other cases the minimum voltage is 3.6V.
Power
Jack
(J15)
3.3V (III)
IC26: ADP5052
Power
Switch
(SW4)
Micro-USB
Port (J11)
VU5V0
J14
IC27: ADR127
REF
VIN
1.25V (III)
Power Source Select
JP7
J14
USB
WALL
BATTERY
EN
PGOOD
1.5A
PVIN1-4
JP7
Power On
LED (LD11)
PVIN5
1.0V (I)
2.1A
1.5V (III)
1.2A
1.8V (II)
0.6A
1.8V (III, analog)
0.1A
IC6: ADP150
0.1A
VIN
3.3V (IV, analog)
EN
R281
D13
Power-on Reset
