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6.2.1.2 PVDD_LDO
The PVDD_LDO provides 3.3 V for all digital pads. It is supplied by VBUS, and requires
a minimum voltage of 4 V to be functional. It delivers a maximum current of 30 mA. The
output of the PVDD_LDO is PVDD_OUT pin. This LDO is used to provide the necessary
supply to PVDD_IN (pad supply for host interface) and PVDD_M_IN (pad supply for
master interfaces). When an external power supply is used, the PVDD_OUT must be
connected to the ground. The ROM boot detects automatically that the LDO output is
connected to the ground, and switches it off. The PVDD LDO has a low power mode,
which is used automatically by the PN7462 family when the chip is in Stand-by mode or
Suspend mode. This enables to supply host pads and GPIOs, and to detect wake-up
signals coming from these interfaces.
6.2.1.3 TXLDO Transmitter supply
The PN7462 family integrates an internal transmitter LDO. The TXLDO can be used to
maintain a constant output voltage for the RF interface. The TXLDO is designed to
protect the chip from voltage ripple introduced by the power supply on the VUP_TX pin. It
is powered through VUP_TX pin. The programmable output voltages are: 3.0 V, 3.3 V,
3.6 V, 4.5 V, and 4.75 V. For a given output voltage, VUP_TX shall always be 0.3V
higher (i.e. to supply a 3 V output, the minimum voltage to be applied on VUP_TX is
3.3 V). If the voltage is no sufficient, then TVDD_OUT follows VUP_TX, lowered of 0.3 V.
When it is not used, TVDD_OUT shall be connected to TVDD_IN, and TX_LDO shall be
turned off. The TXLDO can be used in one of the following power modes
For corresponding register settings, please refer to
6.2.1.4 VCC LDO
The VCC LDO provides contact interface supply VCC.
6.2.1.5 SCLDO
The SCLDO provides a regulated voltage to the DC-to-DC converter, to enable class B
operation when 2.7 < VBUS < 3.9 V and class A operation.
6.2.1.6 DC-to-DC converter
The PN7462 family includes a DC-to-DC converter, in order to support Class A and
Class B cards, when the input voltage VBUSP is not sufficient. The DC-to-DC converter
is a switched capacitance voltage converter. It takes its power from the SCLDO. The DC-
to-DC converter can be bypassed. Its output (VUP) is regulated from 3.3 to 5.5 V.
UM10858
User manual
COMPANY PUBLIC
• Full power mode
• Low power mode
• Low power 2 mode
• Shutdown mode
• Standby mode
All information provided in this document is subject to legal disclaimers.
Rev. 1.4 — 14 May 2018
Section
314514
UM10858
PN7462 family HW user manual
6.7.2.
© NXP B.V. 2018. All rights reserved.
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