 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
LTC2205 Datasheet(PDF) 24 Page - Linear Technology |
|
||||||||||||||||||||||||||||||
LTC2205 Datasheet(HTML) 24 Page - Linear Technology |
|
|
24 / 36 page  LTC2205/LTC2204 24 22054fb PGA Pin The PGA pin selects between two gain settings for the ADC front-end. PGA = 0 selects an input range of 2.25VP-P; PGA = 1 selects an input range of 1.5VP-P. The 2.25V input range has the best SNR; however, the distor- tion will be higher for input frequencies above 100MHz. For applications with high input frequencies, the low input range will have improved distortion; however, the SNR will be worse by up to approximately 2dB to 6dB. See the typical performance curves section. Driving the Encode Inputs The noise performance of the LTC2205/LTC2204 can depend on the encode signal quality as much as on the analog input. The encode inputs are intended to be driven differentially, primarily for noise immunity from common mode noise sources. Each input is biased through a 6k resistor to a 1.6V bias. The bias resistors set the DC oper- ating point for transformer coupled drive circuits and can set the logic threshold for single-ended drive circuits. Any noise present on the encode signal will result in ad- ditional aperture jitter that will be RMS summed with the inherent ADC aperture jitter. In applications where jitter is critical (high input frequen- cies), take the following into consideration: 1. Differential drive should be used. 2. Use as large an amplitude possible. If using trans- former coupling, use a higher turns ratio to increase the amplitude. 3. If the ADC is clocked with a fixed frequency sinusoidal signal, filter the encode signal to reduce wideband noise. 4. Balance the capacitance and series resistance at both encode inputs such that any coupled noise will appear at both inputs as common mode noise. The encode inputs have a common mode range of 1.2V to 3V. Each input may be driven from ground to VDD for single-ended drive. Figure 8. Transformer Driven Encode VDD VDD LTC2205/ LTC2204 22054 F08 VDD ENC– ENC+ 1.6V 1.6V ETC1-1T 0.1 µF 33pF ENCODE INPUT 6k 6k 100 Ω 50 Ω TO INTERNAL ADC CLOCK DRIVERS 0.1 µF 50 Ω • • APPLICATIONS INFORMATION |
Similar Part No. - LTC2205 |
|
Similar Description - LTC2205 |
|
|
Link URL |
| Privacy Policy |
| ALLDATASHEET.COM |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List 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 |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
