3 Hardware Connections

There are two major variants of the BM77 modules:
  • BM77SPPS3MC2-000xxx – Has an integral antenna and shield
  • BM77SPP03MC2-000xxx – Does not have an integral antenna and shield
The BM78 module has corresponding footprint compatible modules:
  • BM78SPPS5MC2-0B06AA – Has an integral antenna and shield
  • BM78SPP05MC2-0B06AA – Does not have an integral antenna and shield

The recommendation is to use the corresponding hardware variants when migrating from the BM77 to the BM78 module to save hardware development effort because they are footprint compatible (see Table 2-2).

The BM78 module also offers ROM variant modules BM78SPPx5NC2-0002AA for shielded/antenna and unshielded/no antenna configurations. The recommendation is to not use the BM78 ROM variant modules for new designs because they do not have the latest security updates and, hence, are not compliant to the latest Bluetooth v 5.0 specifications.

The following figure illustrates the reference schematic for connecting the BM78 module to an MCU. All BM78 module variants (with or without integral antenna and shield) share the same control signals. The corresponding BM77 and BM78 modules listed in Table 2-2 are footprint compatible and do not require a PCB design update for migration.

For the BM77SPP03MC2-000xxx unshielded module (no shield and antenna), migrating to the corresponding BM78SPP05xC2-000xxx module needs a check for the antenna-matching circuit tuning for optimal RF performance. For more details, refer to the BM78 Bluetooth® Dual Mode Module Data Sheet (DS60001380).
Figure 3-1. BM78 Hardware Configuration
Note:
  1. Ensure that the VDD_IO and MCU VDD voltages are compatible.
  2. The control and indication ports are configurable.