CYW20734
1.17 Infrared Learning
The CYW20734 includes hardware support for infrared learning. The hardware can detect both modulated and unmodulated signals.
For modulated signals, the CYW20734 can detect carrier frequencies between 10 kHz and 500 kHz, and the duration that the signal
is present or absent. The CYW20734 firmware driver supports further analysis and compression of the learned signal. The learned
signal can then be played back through the CYW20734 IR TX subsystem (see Figure 7).
Figure 7. Infrared RX
1.18 Power Management Unit
The Power Management Unit (PMU) provides power management features that can be invoked by software through power
management registers or packet-handling in the baseband core.
1.18.1 RF Power Management
The BBC generates power-down control signals for the transmit path, receive path, PLL, and power amplifier to the 2.4 GHz trans-
ceiver, which then processes the power-down functions accordingly.
1.18.2 Host Controller Power Management
Power is automatically managed by the firmware based on input device activity. As a power-saving task, the firmware controls the
disabling of the on-chip regulator when in HIDOFF (deep sleep) mode.
1.18.3 BBC Power Management
There are several low-power operations for the BBC:
■ Physical layer packet handling turns RF on and off dynamically within packet TX and RX.
■ Bluetooth-specified low-power connection mode. While in these low-power connection modes, the CYW20734 runs on the Low
Power Oscillator and wakes up after a predefined time period.
The CYW20734 automatically adjusts its power dissipation based on user activity. The following power modes are supported:
■ Active mode
■ Idle mode
■ Sleep mode
■ HIDOFF (deep sleep) mode
The CYW20734 transitions to the next lower state after a programmable period of user inactivity. When user activity resumes, the
CYW20734 immediately enters Active mode.
In HIDOFF mode, the CYW20734 baseband and core are powered off by disabling power to VDDC_OUT and PAVDD. The VDDO
domain remains powered up and will turn the remainder of the chip on when it detects user events. This mode minimizes chip power
consumption and is intended for long periods of inactivity.
Document Number: 002-14874 Rev. *S
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