User's Manual l MBa7x UM 0101 l © 2020, TQ-Systems GmbH
Page 20
4.1.7
Power supply
DC Jack +
2-pin terminal
X26 / X27
V
IN
(24 V / 3.5 A)
Protective
circuitry
Switching
regulator
VCC5V
VCC3V3
Switching
regulator
VCC12V
Switching
regulator
VCC1V5
VCC5V
VCC3V3
VCC1V5_MPIE (max. 0.375 A)
VCC12V
Mini PCIe
(X17)
VCC3V3_MPCIE (max. 1.1 A)
LVDS-CMD
DF19 connector
(X16)
Headers
(X23, X24, X25)
Per voltage:
3.3 V: 2 A max. load
5 V: 2 A max. load
12 V: 3 A max. load
Switch
VCC3V3
LinReg
VCC2V5
LinReg
VCC1V0
Ethernet 1
Ethernet 2
VCC2V5_ETH
VCC1V0_ETH
24 V
Figure 8:
Block diagram power supply
The MBa7x is supplied with 24 V via X26 or X27. From this voltage 1.0 V, 1.5 V, 2.5 V, 3.3 V, 5 V and 12 V are generated on the
MBa7x. These voltages are used to supply the components on the MBa7x.
Additionally, 3.3 V, 5 V and 12 V are available at each of the three headers (X23, X24, and X25). 5 V and 12 V are available at the
LVDS-CMD connector (X16). All five connectors share the available power (2 A @ 3.3 V, 2 A @ 5 V, 3 A @ 12 V).
The PCIe connector is supplied with 1.5 V and 3.3 V. 1.5 V is generated from 5 V and is only available at the PCIe connector.
The 1.5 V rail can supply 0.375 A, the 3.3 V rail can supply 1.1 A.
When VCC12V_EN is High, VCC12V is powered. When VCC12V_EN is Low, VCC12V is switched off.
Attention:
Usage of VCC3V3_MB_EN
The VCC3V3 power supply on the carrier board should be switched with signal VCC3V3_MB_EN
by the TQMa7x, to avoid cross supply and errors in the power-up/down sequence.
9:
Attention: When the PMIC is switched off, the voltage VCC3V3_REFOUT (from the TQMa7x) drops to approx. 2.7 V due to cross-supply effects
of the still activated 3.3 V (on the MBa7x). It must be ensured that the circuitry can respond to this level.
