ATmega406 Atmel Corporation, ATmega406 Datasheet - Page 136

• Manufacturer Part Number: ATmega406
• Manufacturer: Atmel Corporation

Specifications of ATmega406

• Flash (kbytes): 40 Kbytes
• Pin Count: 48
• Max. Operating Frequency: 1 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 8
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 18
• Ext Interrupts: 4
• Usb Speed: No
• Usb Interface: No
• Twi (i2c): 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 11
• Adc Resolution (bits): 12
• Adc Speed (ksps): 1.9
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 2
• Eeprom (bytes): 512
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -30 to 85
• I/o Supply Class: 4.0 to 25
• Operating Voltage (vcc): 4.0 to 25
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 3
• Pwm Channels: 2
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

24. Cell Balancing
136
ATmega406
ATmega406 incorporates cell balancing FETs. The chip provides one cell balancing FET for
each battery cell in series. The FETs are directly controlled by the application software, allowing
the cell balancing algorithms to be implemented in software. The FETs are connected in parallel
with the individual battery cells. The cell balancing is illustrated in
a four-cell configuration. The cell balancing FETs are disabled in the Power-off mode.
Typical current through the Cell Balancing FETs (T
controlled by the CBCR. Neighbouring FETs cannot be simultaneously enabled. If trying to
enable two neighbouring FETs, both will be disabled.
Figure 24-1. Cell Balancing
RP
RP
RP
RP
RP
T
T
T
T
CB
CB
CB
CB
PV4
PV3
PV2
PV1
NV
Level
Shift
Level
Shift
Level
Shift
Level
Shift
CB
) is 2 mA. The Cell Balancing FETs are
Control Register
Cell Balancing
Figure
24-1. The figure shows
2548E–AVR–07/06