Port Id Resistor Values - Freescale Semiconductor i.MX53 Quick Start Manual

Hardware Reference Manual for i.MX53 Quick Start
MCIMX28LCD
MCIMXHDMICARD
Over‐Voltage protection is sensed by the DCIN (B4) pin of the PMIC. The voltage sensed by this pin must
be between 4.5V and 5.5V. If the voltage meets this threshold value, the voltage seen at DCIN is blocked
from the DCIN_SEL (B3) pin and the P‐Channel MOSFET turns ON. Otherwise, DCIN_SEL remains high
and power is blocked from the rest of the Quick Start Board.
The TP (L5) pin of the PMIC must be connected to ground. When designing with a 0.5mm pitch uBGA
package, there is limited space for vias and traces under the BGA. To assist with layout, Freescale has
confirmed that all pins labeled 'NO CONNECT' on the PMIC are in no manner bonded out to the silicon.
Therefore, for routing purposes, it is possible to route the trace from an interior pin through one or
more 'NO CONNECT' pins, or to place a via directly under a 'NO CONNECT' pin without requiring a via‐in‐
pad technique. If the CAD Layout Engineer decides to place a via under a 'NO CONNECT' pin, the via
should not be tented as trapped gases during the assembly process may cause the solder ball from the
'NO CONNECT' pin to blow out into other pins and cause internal shorts under the BGA.
The I2C communications channel between the Processor and the PMIC is Channel 1. This channel is only
shared with the accelerometer. This channel operates at TTL logic level of 1.8V. The NRESET (F10) pin of
the PMIC is directly connected to the Active Low POR_B (C19) pin of the i.MX Processor. The PMIC will
hold the Processor in the RESET state until all the power rails are fully powered. The NIRQ (E10) pin of
the PMIC is connected to the GPIO_ 16 (C6) pin of the Processor. This pin is not a dedicated pin for an
interrupt request, but can be programmed in Software to inform the Processor that the PMIC has
information to be given to the Processor.
The PMIC has several different options for Pull‐Up levels on each of its output pins. In some cases,
VDDOUT is one option, along with power supplied to both the VDD_IO1 (L4) and VDD_IO2 (K4) pins as
Pull‐Up source. The exact source of Pull‐Up power is determined by the registry settings of the PMIC and
can be pre‐programmed at the factory as the designer wishes. Some Pull‐Up registry settings apply to
groups of pins, so care must be made in selecting which source power source is used for a particular
grouping of pins. The Dialog PMIC Datasheet contains much more detailed information on the registry
settings. For the Quick Start board, VLDO3 (3.3V) is connected to VDD_IO1 primarily to ensure that the
3V3_EN signal sent to the external regulator is sufficient to turn on the regulator, and VLDO8 (1.8V) is
connected to VDD_IO2 to provide for proper I2C TTL logic levels.
Freescale Semiconductor
Hardware User Guide for i.MX53 Quick Start Board,
PORT_ID0 Measured Voltage
18.0K 1.61 V
2.74K 0.54 V
Table 3.
PUBI – Public Use Business Information
PORT_ID1 Measured Voltage
130.0K
130.0K
Port ID Resistor Values
Preliminary Rev 0.91
2.32 V
2.32 V
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