xe3006 Semtech Corporation, xe3006 Datasheet - Page 11

• Manufacturer Part Number: xe3006
• Description: Sandman? Codec | Semtech
• Manufacturer: Semtech Corporation

The above illustration is valid for either the SMAD output as a result of AIN/SDO or for the SMDA output as a
function of AOUT/SDI.
2.1.10 Start-up and Initialization
The CODEC generates its own power on reset signal after a power supply is connected to the VDD pin. The reset signal
is made available for the user at the pin NRESET. The rising edge of the NRESET indicates that the startup sequence of
the CODEC has finished. In most applications the NRESET pin can be left open.
The NRESET signal generated by the CODEC is used to initialize the various blocks in the device and guarantees a
correct start-up of the circuit. The start-up sequence that is automatically carried out upon power-up of the device is listed
below and illustrated in Figure 10.
The user can use the NRESET pin in 3 different ways and combinations:
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1. NRESET is low (0V) when the device is not powered and remains low for a short time when VDD (upper curve in
2. As soon as the MCLK signal is present, a counter is activated that counts 2
Figure 10) is applied. The low state sustains while VDD, VREG16, VREF are stabilizing.
moment the NRESET is in the high state (VDD).
NRESET
MCLK
Figure 11: Startup sequence and NRESET signal after power-on.
977 ms (MCLK=2.048KHz)
11
main reset
. . .
VDD = 1.8..3.3V
VREG16 = 1.6V
VREF = 1.2V
21
XE3005/XE3006
periods of the MCLK. After this
time
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