AnsweredAssumed Answered

SSM2529 Reflections

Question asked by ManuelJ on Nov 14, 2013
Latest reply on Nov 7, 2014 by DaveThib


I've trouble configuring the SSM2529. Fault description:

Playing a sine sweep and hearing multiple reflections of the Signal (see picture, sine at 8KHz),

also Signals cuts off at 15KHz.


my configuration:

I2S Signal 44,1 KHz, 32Bit

BCLK as source (44,1 kHz * 2 * 32), DPLL_NDIV=2 (*4), X = 2, R = 5, N=1, M=1

autodetect frequency.

(PLLs are locked)


Additional questions:

-chip is working even if DPLL_NDIV=1 (APPL input < 8 MHz)

-not all possible combination of PLL parameters are working, even if freq is listed in table 48 (MCLK ratio)

-Function of FSYS_DPLL(APLL_CTRL6)

-Function of Bit 0 (APLL operation mode) in APLL_CTRL5 REGISTER





Added original sine sweep and recorded one for comparisation.

Complete registerset SSM2529: (all other values are resetvalues)  


Reg. Val.


0x0 0x24

0x1 0x21

0x2 0x02

0x3 0x00

0x4 0x10

0x5 0x70

0x6 0x70

0x7 0x20

0x8 0x1A

0x9 0x00

0xA 0x00

0xB 0x00

0xC 0x00

0xD 0x28

0xE 0x03


0x14 0x05

0x10 0x28