ia3513 integration, ia3513 Datasheet - Page 15

• Manufacturer Part Number: ia3513
• Description: Headset Voice And Power Solution
• Manufacturer: integration

IA3513
CLOCK GENERATOR
Description
The clock generator block, comprises a 26 MHz crystal oscillator and an internal low power 32 kHz oscillator. Various modes of
operation are available for the generation of the 32 kHz clock, including division from the 26 MHz clock, when this clock is
available and direct output from the calibrated 32 kHz internal oscillator.
Trimming of the 26MHz oscillator is available using 6 bits in register 23.
The 26MHz Oscillator is powered on and off by the Clk26Rqst input signal, the 32kHz clock is on by default but can be disabled
using the I2C interface.
Clock Generator Functional Block Diagram
32kHz Oscillator Functional Description
The 32kHz oscillator is composed by 3 main blocks, a calibration state machine, a divider and a low power oscillator (LPO) with
low temperature coefficient and high PSR in order to achieve the 250ppm accuracy specification.
During calibration the state machine compares the LPO frequency with the 26Mhz frequency generated by the crystal oscillator,
in order to determine the correct modulo for the divider. At the end of a calibration cycle, the new divider modulo is loaded into
the divider to obtain the 32kHz output.
32kHz Oscillator Functional Block Diagram
26Mhz
Calibration
clock
State
Internal
Machine
LPO
32kHz Oscillator out
Divider
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