Ultra-Low-Power Microcontrollers
MC9S08QB8/4: Simplicity with Substance
Taking the lead in low power
Target Applications
• Battery-powered applications
• Residential/commercial garage
• Smoke detectors
• Remote window shutters
• Remote control applications
• Battery-operated toys and games
Overview
Achieving raw performance is no longer the
number one issue—it’s now “performance within
an energy budget.” Freescale understands this
challenge and offers a wide portfolio of S08
devices that help you reach target performance
levels while minimizing low power in your
design. The QB family demonstrates extreme
energy efficiency for ultra-long operating life
in battery-powered applications.
As a subset of QE family, the QB8 16-pin TSSOP
and 28-pin SOIC are pin compatible with the
QE8 device. The S08QB8 (QB8) microcontroller
offers low-power features such as two ultra-
low-power stop modes, new low-power run and
wait modes, 6 μs wake-up time, ultra-low-power
external oscillator and clock gating registers to
disable clocks to unused peripherals.
The QB8 offers up to 8 KB of flash memory
and an 8-channel, 12-bit resolution analog-
to-digital converter (ADC). The S08QB8 can
be powered down to 1.8V and still able to
operate at maximum 20 MHz CPU speed. QB8
consists of a 8-bit modulo timer, a 16-bit timer/
pulse width modulator, UART, real time counter,
analog comparator, 8-channel keyboard interrupt
module—perfect for cost-effective, battery
sensitive, portable, low-power applications.
door openers
Power-Saving Features
• Clock gating disables clocks to unused peripherals
8-bit HCS08 Central Processing Unit (CPU)
On-Chip Memory
Features
• Two ultra-low-power stop modes, one of which
• New low-power run and wait modes
• 6 µs typical wake up time from stop mode
• Internal clock Source (ICS)—module containing a
• Oscillator (OSC)—loop-control Pierce oscillator;
• Up to 20 MHZ HCS08 CPU from 1.8V to 3.6V and
• HCS08 instruction set with added BGND instruction
• Up to 8 KB flash read/program/erase over full
• Up to 512 bytes of random access memory(RAM)
Debugging/Interface
allows limited use of peripherals
frequency locked-loop (FLL) controlled by internal
or external reference
crystal or ceramic resonator range of 31.25 kHz to
38.4 kHz or 1 MHz to 16 MHz
across temperature range of -40°C to +85°C
operating voltage and temperature
with low ram retention voltage and security feature
Peripherals
Flash/ROM
• Provides flexibility to turn off individual modules
• Reduces power consumption
Benefits
• Allows continued application sampling in a reduced
• Allows use of all chip peripherals in a low-power state
• Enables faster execution out of stop modes
• Provides choice of frequencies on the fly. Reducing
• Includes ultra-low-power OSC for accurate
• Offers high performance, even at low voltage levels
• Provides bus speed operation of 10 MHz from
• Easy to learn and use architecture
• Backward object code compatibility with 68HC08 and
• Allows for efficient, compact module coding in
• Allows user to take full advantage of
• RAM can hold content with low voltage supply.
• Security circuitry prevents unauthorized access to
power state which extends battery life
frequency saves current.
timebase in low-power modes
for battery-operated applications
1.8V to 3.6V
68HC05 for reuse of existing libraries can still be used
assembly or C compiler
in-application, reprogrammability benefits in
virtually any environment
This reduces over all power consumption.
RAM and flash content.
RAM
Core plus Feature
8-bit Fact Sheet