EVAL-ADAU1701EB AD [Analog Devices], EVAL-ADAU1701EB Datasheet - Page 16

• Manufacturer Part Number: EVAL-ADAU1701EB
• Description: SigmaDSP 28/56-Bit Audio Processor with 2ADC/4DAC
• Manufacturer: AD [Analog Devices]

ADAU1701
Two specifications need to be taken into consideration when
choosing a regulator transistor. First, the transistor’s current
100 nF
Figure 18. Voltage Regulator Design
10 uF
DVDD
VDRIVE
3.3V
ADAU170 1
1 kΩ
Rev. PrF | Page 16 of 43
amplification factor (h
the transistor’s collector needs to be able to dissipate the heat
generated when regulating from 3.3 V to 1.8 V. The maximum
digital current draw of the ADAU1701 is 60 mA. The equation
to determine the transistor’s minimum power dissipation specs
is as follows:
There are many transistors with these specifications available in
small packages (i.e. SOT-23 or SOT-223), such as the 2N3906 or
FZT953.
(3.3 V – 1.8 V) × 60 mA = 90 mW
Preliminary Technical Data
FE
or beta) should be at least 100. Second,