AN91267 Datasheet, PDF (49/62 Pages) Ramtron International Corporation – Getting Started with PSoC

Getting Started with PSoC® 4 BLE
Applications
Industrial
Home Automation
Analog Peripherals
ADC: Differential mode (temperature measurement)
IDAC (temperature-sensor drive)
Low-Power Comparator (wakeup on threshold detection)
Opamp: PGA (4-mA to 20-mA current-loop system)
Opamp: PGA (motion sensor, light sensor)
Comparator (door sensors)
ADC and opamp filter (smoke detector)
System-Wide Resources
This section explains the system-wide resources available for all peripherals in PSoC 4 BLE.
Low-Leakage Power Modes
PSoC 4 BLE offers the following power modes. Note that these are PSoC 4 BLE device power modes, which are different from
the power modes described in the Bluetooth Low Energy Subsystem (BLESS) section.
 ^{Active mode: This is the primary mode of operation. In this mode, all peripherals are available.}
 ^{Sleep mode: In this mode, the CPU is in Sleep mode, SRAM is in retention, and all peripherals are available. Any}
interrupt wakes up the CPU and returns the system to Active mode.
 Deep-Sleep mode: In this mode, the high-frequency clock (IMO) and all high-speed peripherals are off. Optionally, the
low-frequency clocks (32-kHz ILO and WCO) and low-speed peripherals are available. Interrupts from low-speed,
asynchronous, or low-power analog peripherals can cause a wakeup. The current consumption in this mode is 1.3 µA.
 Hibernate mode: This power mode provides a best-in-class current consumption of 150 nA while retaining SRAM and the
ability to wake up from an interrupt generated by a low-power comparator or a GPIO.
 Stop mode: This power mode retains the GPIO states. Wakeup is possible from a fixed WAKEUP pin. The current
consumption in this mode is only 60 nA.
You can use a combination of Sleep, Deep-Sleep, Hibernate, and Stop modes in a battery-operated BLE system to achieve
best-in-class system power with longer battery life.
Table 6 shows the dependency between PSoC 4 BLE system power modes and BLESS power modes. All these
dependencies are handled by simple APIs; see the Main Loop and Low-Power section for an example.
In a typical BLE application such as heart-rate monitoring, the PSoC 4 BLE device will be in Active mode while measuring the
heart rate, in Sleep mode while the BLE radio is transmitting or receiving packets, in Deep-Sleep mode between consecutive
BLE connection intervals, and in Hibernate or Stop mode on BLE advertisement timeout.
Table 6. PSoC 4 BLE Power Modes
PSoC 4 BLE System Power Modes
BLESS Modes _{Active Sleep Deep-Sleep Hibernate Stop}
Transmit
 


Receive
 


Idle
 


Sleep
 


Deep-Sleep





Powered
 


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Document No. 001-91267 Rev. *D
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