Data Sheet

Document Number: 002-28053 Rev. ** Page 12 of 47
CYBT-343052-02
Connections and Optional External Components
Power Connections (VDDIN)
The CYBT-343052-02 contains one power supply connection, VDDIN, which accepts a supply input range of 2.3 V to 3.6 V for
CYBT-343052-02. Table 12 provides this specification. The maximum power supply ripple for this power connection is 100 mV, as
shown in Table 12.
It is not required to place any power supply decoupling or noise reduction circuitry on the host PCB. If desired, an external ferrite bead
between the supply and the module connection can be included, but is not necessary. If used, the ferrite bead should be positioned
as close as possible to the module pin connection and the recommended ferrite bead value is 330 , 100 MHz.
Considerations and Optional Components for Brown Out (BO) Conditions
Power supply design must be completed to ensure that the CYBT-343052-02 module does not encounter a Brown Out condition,
which can lead to unexpected functionality, or module lock up. A Brown Out condition may be met if power supply provided to the
module during power up or reset is in the following range:
V
IL
VDDIN V
IH
Refer to Table 13 for the V
IL
and V
IH
specifications.
System design should ensure that the condition above is not encountered when power is removed from the system. In the event that
this cannot be guaranteed (that is, battery installation, high-value power capacitors with slow discharge), it is recommended that an
external voltage detection device be used to prevent the Brown Out voltage range from occurring during power removal. Refer to
Figure 8 for the recommended circuit design when using an external voltage detection IC.
Figure 8. Reference Circuit Block Diagram for External Voltage Detection IC
In the event that the module does encounter a Brown Out condition, and is operating erratically or is not responsive, power cycling
the module will correct this issue and once reset, the module should operate correctly. Brown Out conditions can potentially cause
issues that cannot be corrected, but in general, a power-on-reset operation will correct a Brown Out condition.
External Reset (XRES)
The CYBT-343052-02 has an integrated power-on reset circuit, which completely resets all circuits to a known power-on state. This
action can also be evoked by an external reset signal, forcing it into a power-on reset state. The XRES signal is an active-low signal,
which is an input to the CYBT-343052-02 module (solder pad 3). The CYBT-343052-02 module
does not require an external pull-up
resistor on the XRES input
During power-on operation, the XRES connection to the CYBT-343052-02 is required to be held low 50 ms after the VDD power supply
input to the module is stable. This can be accomplished in the following ways:
■ The host device should connect a GPIO to the XRES of the Cypress CYBT-343052-02 module and pull XRES low until VDD is
stable. XRES is recommended to be released 50 ms after VDDIN is stable.
■ If the XRES connection of the CYBT-343052-02 module is not used in the application, a 10-µF capacitor may be connected to the
XRES solder pad of the CYBT-343052-02 to delay the XRES release. The capacitor value for this recommended implementation
is approximate, and the exact value may differ depending on the VDDIN power supply ramp time of the system. The capacitor value
should result in an XRES release timing of 50 ms after VDDIN stability.
■ The XRES release timing may be controlled by an external voltage detection IC. XRES should be released 50 ms after VDD is stable.
Refer to Figure on page 18 for XRES operating and timing requirements during power-on events.