KX1400EW Keterex, KX1400EW Datasheet - Page 17

• Manufacturer Part Number: KX1400EW
• Description: Audio D/A Converter ICs KX1400 Audio Playback IC
• Manufacturer: Keterex

Specifications of KX1400EW

• Resolution: 12 bit
• Operating Supply Voltage: 2.7 V to 5.5 V
• Operating Temperature Range: - 40 C to + 85 C
• Maximum Power Dissipation: 120 mW
• Mounting Style: SMD/SMT
• Number Of Dac Outputs: 2
• Power Consumption: 320 mW
• Supply Current: 50 mA
• Thd Plus Noise: 40 dB
• Package / Case: SOIC-20
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

a Set Duration command via the MCU host interface or as part of a phrase processed from external
memory. Once configured, the duration value remains in effect for all subsequent Play Tone commands
or until a new duration is set. It is possible to issue a Set Duration command before each new Play Tone
command, thereby allowing each tone in a sequence to have a different duration.
SPO- pins.
A mute feature is provided to save power when not producing sound and to prevent possible speaker
pops and clicks during device power-on/off. The mute feature disconnects the internal speaker driver
amplifiers from the SPO+ and SPO- output pins and terminates them to ground.
The mute feature is controlled by sending Mute and Un-mute commands via the MCU host interface or as
part of a phrase processed from external memory. A stepping algorithm is employed which gradually
ramps the speaker output up/down between the currently configured volume level and the zero output
level. The output is ramped at a rate of one volume level increment every 1 ms. During power-up or after
a device reset, the speaker driver is muted and the volume level set to full volume. It is recommended
the speaker driver be muted before powering down or resetting the device if possible. Refer to Section 8
for more information regarding the Mute and Un-mute commands.
The Frequency Index takes a value from 0 to 16383. Therefore, frequencies can be generated in the
range of 0.24414 Hz to 3.9997 KHz. A Frequency Index of 0 causes the KX1400 IC to repeat the
previous tone but mute the output for the duration of the tone. This allows the IC to generate a controlled
period of silence. The outputs are automatically un-muted when the next audio command is processed.
6.7.2. Tone Duration
The length of time each tone is played is determined by the currently configured duration value. The
duration value represents time in milliseconds and may be configured with a value from 0 to 4095.
Therefore, tone durations may range from 1 millisecond to 4.095 seconds in 1 millisecond increments.
Durations longer than 4.095 seconds can be created by repeating the Play Tone command in order to
extend the playing of a tone.
At the end of the duration period, any pending audio command will execute.
generator will halt and speaker driver output will return to a DC average (no tone).
corresponds to an infinite duration (tones will play until a Reset, Stop or new audio command, such as
another Play Tone command, is issued).
After reset, the default duration value is 0 (infinite duration). The duration value is configured by sending
6.8. Speaker Driver
The KX1400 includes a speaker driver suitable for driving an 8-ohm (or greater) speaker directly. The
speaker driver incorporates a class-D amplifier stage with differential outputs connected to the SPO+ and
6.9. On-chip Oscillator
The KX1400 includes a factory calibrated, internal 8.2 MHz oscillator used as the system time base. No
external components are necessary for calibration or operation. Electrical specifications for the precision
internal oscillator are given in Table 6.6 Specifications are for T
unless otherwise specified.
KX1400 Audio Playback IC
A
= -20
°
C to +70
°
C, VDD = 2.7V to 5.5V
Otherwise, the tone
A value of 0
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