ATtiny43U Atmel Corporation, ATtiny43U Datasheet - Page 46

• Manufacturer Part Number: ATtiny43U
• Manufacturer: Atmel Corporation

Specifications of ATtiny43U

• Flash (kbytes): 4 Kbytes
• Pin Count: 20
• Max. Operating Frequency: 8 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 8
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 16
• Ext Interrupts: 16
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 4
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 0.25
• Eeprom (bytes): 64
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: Yes
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 0.7 to 5.5
• Operating Voltage (vcc): 0.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 4
• Pwm Channels: 4
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

8.7
8.8
8.9
8.10
46
Typical Applications
Characteristics
Potential Limitations
Bypassing the Boost Converter
ATtiny43U
A typical use of the boost converter is illustrated in
optimized depending on the type of application.
three different types of applications (cost effective, high output current and long battery life). All
values are guidelines, only.
Table 8-2.
Notes:
Electrical characteristics of the boost converter are given in
characteristics can be found under section
When the device is powered via the boost converter some usage limitiations may apply. For
example, the highest allowed operating frequency of the device depends on supply voltage (see
“Speed Grades” on page
given in
into Active Low Current Mode the supply voltage will drop periodically, affecting the maximum
allowed operating frequency.
Provided the load current remains sufficiently high the boost converter will never enter Active
Low Current Mode and the supply voltage will remain high enough to run the device at higher
frequencies. The boost converter status bit BS can be used to determine if the boost converter is
in Low Current Mode (see
Since the entire device is powered from the boost converter output variations will show in all
peripherals. This means that, for example, high levels of I/O pins may vary with supply voltage.
It is possible to bypass and disable the boost converter so that the device can be powered
directly from an external supply. To force the boost converter into Stop Mode, connect pin V
to ground and provide the device with supply directly to the V
Symbol
L
D
R
C
C
C
C
1
1
1
1
2
3
4
1. Low ESR required.
2. High reverse leakage current, increases current consumption.
3. The diode is the largest individual contributor to battery life. The example diode keeps the
4. Depends on internal resistance of power supply.
5. Depends on load current. May not be sufficient for maximum current rating.
Table 20-7 on page
boost converter running and maintains a reasonable efficiency level.
Component
Inductor
Schottky diode
Resistor
Input Capacitor
Secondary Input Cap.
Output Capacitor
Secondary Output Cap.
Recommended Components and Values for Various Designs
156) and the boost converter output voltage varies within the limits
“ADCSRB – ADC Control and Status Register B” on page
159. This means that if the design allows the boost converter to go
Cost Effective
10MQ100N
“Boost Converter” on page
10
1
680
100
15
–
(4)
(5)
Table
Figure 8-2 on page
8-2, below, presents recommendations for
High Current
10BQ015
15
100
680
CC
4.7
22
22
Table 20-7 on page
(1)
pin. To permanently disable the
(2)
165.
37. Components can be
Battery Life
10BQ040
15
680
100
4.7
22
22
(1)
8048B–AVR–03/09
(3)
159. Typical
47).
Unit
µH
µF
nF
µF
nF
Ω
BAT