Cirrus Logic CS4234 - Manual (Page 11)

DS899F1 11
CS4234
TYPICAL CURRENT CONSUMPTION
This table represents the power consumption for individual circuit blocks within the CS4234. CS4234 is configured as
shown in
Figure 2 on page 8 . VA_SEL = 0 for VA = 3.3 VDC, 1 for VA = 5.0 VDC; F
S
= 100 kHz; MCLK = 25.6 MHz;
DAC load is 3 k ; All input signals are zero (digital zero for SDINx inputs and AC coupled to ground for AINx
inputs) .
Notes:
8. Full-scale differential output signal.
9. Current consumption increases with increasing F
S
and increasing MCLK. Values are based on F
S
of
100 kHz and MCLK of 25.6 MHz. Current variance between speed modes is small.
10. PLL is activated by setting the MCLK RATE bit to either 000 (operating in 256x mode) or 001 (operating
in 384 kHz).
11. Internal to the CS4234, the analog to digital converters are grouped together in stereo pairs. ADC1 and
ADC2 are grouped together as are ADC3 and ADC4. The ADC group current draw is the current that
is drawn whenever one of these groups become active.
12. To calculate total current draw for an arbitrary amount of ADCs or DACs, the following equations apply:
Total Running Current Draw from VA Supply = Power Down Overhead + PLL (If Applicable)+ DAC Current Draw + ADC Current Draw
where
DAC Current Draw = DAC Overhead + (Number of DACs x DAC Channel)
ADC Current Draw = ADC Overhead + (Number of active ADC Groups x ADC Group) + (Number of active ADC Channels x ADC Channel)
and
Total Running Current Draw from VL Supply = PDN Overhead + (Number of active ADC Channels x ADC Channel)
Typical Current [mA]
(unless otherwise noted)
(Note 9) , (Note 12)
Functional Block
VA/VL i
VA
i
VL
1
Reset Overhead
(All lines held static, RST line pulled low.) 5 0.030 0.001
3.3 0.020 0.001
2
Power Down Overhead
(All lines clocks and data lines active, RST line pulled high, All PDNx bits set high.) 5 5 0.101
3.3 5 0.101
3
PLL (Note 10)
(Current drawn resulting from PLL being active. PLL is active for 256x and 384x)
5 1 -
3.3 1 -
4
DAC Overhead
(Current drawn whenever any of the five DACs are powered up.) 5 50 -
3.3 45 -
5
DAC Channel (Note 8)
(Current drawn per each DAC powered up.)
5 5 -
3.3 4 -
6
ADC Overhead
(Current drawn whenever any of the four ADCs are powered up.) 5 11 -
3.3 11 -
7
ADC Group
(Current drawn due to an ADC “group” being powered up. See
(Note 11) )
5 2 -
3.3 2 -
8
ADC Channel
(Current drawn per each ADC powered up.) 5 2 0.109
3.3 2 0.066