ATTINY43U-MU Atmel, ATTINY43U-MU Datasheet - Page 45

• Manufacturer Part Number: ATTINY43U-MU
• Description: MCU AVR 4K FLASH 8MHZ 20-QFN
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY43U-MU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: USI
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 16
• Program Memory Size: 4KB (2K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 64 x 8
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 4x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 20-MLF®, QFN
• Processor Series: ATTINY4x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 256 B
• Interface Type: SPI
• Maximum Clock Frequency: 8 MHz
• Number Of Programmable I/os: 16
• Number Of Timers: 2
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 4 Channel
• For Use With: ATSTK600-TINYX3U - STK600 SOCKET/ADAPTER TINYX3U
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8.6.5
8.6.6
8048B–AVR–03/09
Output Capacitors
Summary
Too high resistor values may lead to Start Mode failures. See
ues” on page 45
Capacitor C
An output capacitor, C
transferred to the inductor. It is recommended to use a capacitor with high capacitance and low
Equivalent Series Resistance, ESR. A large capacitance helps to reduce the voltage ripple at
the output and a low ESR reduces voltage ripple and helps to keep the temperature of the
capacitor within limits.
The recommended capacitance at a given, steady-state load is calculated as follows:
... where T
and D is the duty cycle, calculated as shown in
The recommended ESR is calculated as follows:
A secondary output capacitor, C
The table below summarises recommended component values for a typical application.
Table 8-1.
Note:
Component
C
C
C
C
D
L
R
1
1
2
3
4
1
1
1. With these values the LPF provides a 32dB attenuation at the switching frequency of the boost
2. Application specific limits may be tighter
S
converter while permitting a supply voltage ripple of about ±200mV
2
is the switching frequency of the boost converter, V
should be located close to the device.
Boost Converter Component Values
for component recommendations and limits.
Recommended Value
C = 4.7µF
C = 100nF
C = 22µF, ESR < 100mΩ
C = 100nF
I
L = 15µH ±20%, I
R = 680Ω
R
= 1µA @ 25°C, V
3
, is required to keep the output voltage stable at times when energy is
(1)
(1)
4
, is recommended and should be placed close to the device.
MAX
C
F
OUT
= 0.5V @ 1A
= 700mA, R < 150mΩ
ESR
=
I
------------------------------------- -
LOAD
≤
“Inductor” on page
-------------- -
I
PEAK
V
V
PP
×
PP
T
S
×
D
“Boost Converter Component Val-
PP
43.
is the allowed voltage ripple
Min
100nF
15µH
10µF
1µF
(2)
Max
100nF
15µH
1kΩ
(2)
45