BCM20730 Datasheet, PDF (23/62 Pages) Cypress Semiconductor – Single-Chip Bluetooth Transceiver for Wireless Input Devices

BCM20730 Data Sheet
Internal Reset
Figure 4: Internal Reset Timing
VDDO
VDDO POR
VDDC
VDDC POR
Baseband Reset
Crystal Enable
VDDO POR delay
~ 2 ms
VDDO POR threshold
VDDC POR threshold
VDDC POR delay
~ 2 ms
Crystal
warm-up
delay:
~ 5 ms
Start reading EEPROM and
firmware boot
Microprocessor Unit
External Reset
The BCM20730 has an integrated power-on reset circuit that completely resets all circuits to a known power-
on state. An external active low reset signal, RESET_N, can be used to put the BCM20730 in the reset state. The
RESET_N pin has an internal pull-up resistor and, in most applications, it does not require that anything be
connected to it. RESET_N should only be released after the VDDO supply voltage level has been stabilized.
Figure 5: External Reset Timing
RESET_N
Baseband Reset
Crystal Enable
Pulse width
>50 µs
Crystal
warm-up
delay:
~ 5 ms
Start reading EEPROM and
firmware boot
BROADCOM ®
September 9, 2013 • 20730-DS108-R
BROADCOM CONFIDENTIAL
Page 22