Datasheet

911
32142D–06/2013
ATUC64/128/256L3/4U
35.8 ABDACB Electrical Characteristics.
Notes: 1. Test Condition: Common Mode Offset Control disabled (CR.CMOC = 0). Alternative Upsampling Ratio disabled
(CR.ALTUPR = 0). Volume at maximum level (VCR0.VOLUME = 0x7FFF and VCR1.VOLUME = 0x7FFF). Device is battery
powered (9V) through an LDO, VDDIO at 3.3V. Analog low pass filter as shown in Figure 35-5(1. order differential low pass
filter followed by a 4. order low-pass), +VCC at +9V and -VCC at -9V. Test signal stored on a SD card and read by the SPI
Interface.
2. Performance numbers for dynamic range, SNR, and THD performance are very dependent on the application and circuit
board design. Since the design has 0dB Power Supply Rejection Ratio (PSRR), noise on the IO power supply will couple
directly through to the output and be present in the audio signal. To get the best performance one should reduce toggling of
other IO pins as much as possible and make sure the device has sufficient decoupling on the IO supply pins.
3. These values are based on simulation and characterization of other AVR microcontrollers manufactured in the same pro-
cess technology. These values are not covered by test limits in production.
Figure 35-5. Differential Analog Low-pass Filter
Table 35-20. Flash Endurance and Data Retention
Symbol Parameter Conditions Min Typ Max Unit
N
FARRAY
Array endurance (write/page) 100k
cycles
N
FFUSE
General Purpose fuses endurance (write/bit) 10k
t
RET
Data retention 15 years
Table 35-21. ABDACB Electrical Characteristics
Symbol Parameter Conditions MIN TYP MAX Unit
Resolution 16 Bits
Dynamic range
(1)(2)(3)
F
S
= 48.000kHz > 76 dB
SNR
(1)(2)(3)
F
S
= 48.000kHz > 46 dB
THD
(1)(2)(3)
F
S
= 48.000kHz < 0.02 %
PSRR 0dB
V
Out
maximum CR.CMOC = 0 97/128 * VDDIO V
V
Out
minimum CR.CMOC = 0 31/128 * VDDIO V
Common mode
CR.CMOC = 0
CR.CMOC = 1, DAC_0 and DAC_1 pins
CR.CMOC = 1, DACN_0 and DACN_1 pins
64/128 * VDDIO
80/128 * VDDIO
48/128 * VDDIO
V
R1, 22K
C2
140p
R2, 22K
R4, 22K
C1, 140p
R3, 22K
R6, 22K
R5, 22K
R7, 22K
C4
270p
C3
310p
-Vcc
+Vcc
-Vcc
+Vcc
DAC
DACN
R8, 22K R9, 22K
C6
110p
C5
750p
-Vcc
+Vcc
GND GND GND GND GND
Out