AK4387 Datasheet, PDF (13/21 Pages) Asahi Kasei Microsystems – 106dB 192kHz 24-Bit 2ch ΔΣ DAC

ASAHI KASEI
[AK4387]
„ System Reset
The AK4387 should be reset once by bringing RSTN pin = “L” upon power-up. The AK4387 is powered up and the
internal timing starts clocking by LRCK “↑” after exiting reset and power down state by MCLK. The AK4387 is in the
power-down mode until MCLK and LRCK are input.
„ Power-down
The AK4387 is placed in the power-down mode by bringing RSTN pin “L” and the anlog outputs become VCOM voltage
(AVDD/2). Figure 6 shows an example of the system timing at the power-down and power-up.
RSTN
Internal
State
D/A In
(Digital)
D/A Out
(Analog)
Clock In
MCLK, LRCK, BICK
DZF
Normal Operation
Power-down
“0” data
GD (1)
(3) (2)
(4)
Don’t care
(6)
Normal Operation
GD (1)
(3)
External
MUTE
(5)
Mute ON
Notes:
(1) The analog output corresponding to digital input has the group delay (GD).
(2) Analog outputs are VCOM voltage (AVDD/2) at the power-down mode.
(3) Click noise occurs at the edge of RSTN signal. This noise is output even if “0” data is input.
(4) The external clocks (MCLK, BICK and LRCK) can be stopped in the power-down mode (RSTN pin = “L”).
(5) Please mute the analog output externally if the click noise (3) influences system application.
The timing example is shown in this figure.
(6) DZF pin is “L” in the power-down mode (RSTN pin = “L”).
Figure 6. Power-down/up Sequence Example
MS0429-E-00
- 13 -
2005/09