ia3513 integration, ia3513 Datasheet - Page 16

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

32 kHz Oscillator Modes of Operation
32 kHz Oscillator Calibration modes
The internal 32kHz oscillator calibration can be done with 2 different approaches.
In continuous calibration mode the internal oscillator is always running calibration cycles whenever the 26MHz clock is available,
this is the default mode.
If desired, calibration can also be run on request by I2C command, although the use of this mode is not advised.
Independently of the calibration mode selected a calibration cycle is done after the rising edge of Clk26Rqst in order to enable
correct sniff mode operation. This initial calibration cycle is only disabled if the calibration is turned off by register write to
register 24.
The 32kHz internal oscillator control is done trough I2C using register 24.
When the 26MHz oscillator is enabled the 32kHz clock is generated by direct division of this clock. The transition between clock
domains,26MHz division and internal oscillator, is guaranteed to be glitchless.
• Continuous Calibration
• Calibration on Request
1) Power Up
2) 26MHz Oscillator on Direct division Mode
3) Calibrated Operation
C lk 2 6 R q s t
C lk 2 6 O u t
C lk 3 2 O u t
In this mode the frequency of the Clk32Out output is guaranteed to be below 50kHz.
The specification for the Clk32kHz clock is stated on the Electrical Characteristics table.
During a time frame of up to 1.28s after the calibration of the 32 kHz Oscillator, the specification for the Clk32Out clock
is stated on the Electrical Characteristics table.
This mode is valid after power up before any calibration has occurred.
8 .6 5 m s
//
//
//
Clk26Rqst
Clk26Out
Clk32Out
+ /-1 0 p p m p re c is io n 2 6 M H z
(F re q u e n c y n o t to s c a le )
(F re q u e n c y n o t to s c a le )
C L K 3 2 k H z C a lib ra tio n
8.65ms
2 m s
//
Continuous mode calibration
//
//
Calibration in sniff mode
+/-10ppm precision 26MHz
(Frequency not to scale)
(Frequency not to scale)
CLK 32kHz Calibration
2ms
N x C L K 3 2 k H z C a lib ra tio n
N x 2 m s
C L K 3 2 k H z C a lib ra tio n
? m s
u n fin is h e d
IA3513
16