| поискавой системы для электроныых деталей |
|
WM8976 датащи(PDF) 78 Page - Wolfson Microelectronics plc |
|
|
|||||||||||||||||||||||||||||
WM8976 датащи(HTML) 78 Page - Wolfson Microelectronics plc |
|
78 / 108 page ![]() WM8976 Pre-Production w PP Rev 3.0 April 2006 78 Notes: 1. This step enables the internal device bias buffer and the VMID buffer for unassigned inputs/outputs. This will provide a startup reference voltage for all inputs and outputs. This will cause the inputs and outputs to ramp towards VMID (NOT using output 1.5x boost) or 1.5 x (AVDD/2) (using output 1.5x boost) in a way that is controlled and predictable (see note 2). 2. Choose the value of the VMIDSEL bits based on the startup time (VMIDSEL=10 for slowest startup, VMIDSEL=11 for fastest startup). Startup time is defined by the value of the VMIDSEL bits (the reference impedance) and the external decoupling capacitor on VMID. 3. Setting DACEN to off while operating in x1.5 boost mode will cause the VMID voltage to drop to AVDD/2 midrail level and cause an output pop. In addition to the power on sequence, it is recommended that the zero cross functions are used when changing the volume in the PGAs to avoid any audible pops or clicks. V pora DGND Internal POR active Device Ready No Power V por_off Power Supply POR I2S Clocks ADC Internal State t midrail_on Analogue Inputs ADCDAT pin GD ADCEN bit Power down Init Normal Operation Normal Operation Init PD Power down ADC enabled ADC enabled ADC off t adcint DNC INPPGAEN bit t adcint INPPGA enabled DNC GD GD GD POR POR Undefined VMID enabled VMIDSEL/ BIASEN bits AVDD/2 t midrail_off (Note 1) (Note 2) (Note 3) (Note 4) V por_on Figure 38 ADC Power Up and Down Sequence (not to scale) SYMBOL MIN TYPICAL MAX UNIT tmidrail_on 500 ms tmidrail_off >10 s tadcint 2/fs n/fs ADC Group Delay 29/fs n/fs Table 64 Typical POR Operation (typical values, not tested) |
|
ссылки URL |
| Вашему бизинису помогли Аллдатащит? [ DONATE ] |
Что такое Аллдатащит | реклама | контакт | Конфиденциальность | Ссылка на техническое описание | обмен ссыками | поиск по производителю All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |