ADuC7129 DAC and DDS

Question

Hi, 
 I have problem witch my DDS on ADuC7129. 
 I wrote functions to start, set freg and stop DDS. Problem is witch current consumptions. After turn on and turn off DDS current consumption increase by 15 mA. What is the reason of this? Hear is my code: 
 void dds_init(){ 
 DACKEY0 = 0x07; 
 DACEN = 0; 
 DACKEY1 = 0xB9; 
 DACCON = 0x0026; 
 } 
 void dds_set_frequency(unsigned long frequency){ 
 DDSFRQ = frequency; 
 } 
 
 void dds_set_phase(unsigned int phase){ 
 DDSPHS = phase & 0x0FFF; 
 } 
 void dds_start(unsigned int scale_ratio){ 
 DDSCON = 0x20 + scale_ratio; 
 } 
 void dds_stop(){ 
 DDSCON = 0x00; 
 DACCON = 0x00; 
 }

ADIApproved · Accepted Answer

The max. spec for normal mode is 49mA. A additional current of up to 30mA can be drawn by the Line Dirver. 
 So if there is some additional current flowing out of GPIOs the current is realistic. Possibly you can reduce in your configuration the current, if you don't set bit 5 in DACCON, because you use the VDACout and not the Line Driver.)

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ADuC7129 DAC and DDS