Moteur de recherche de fiches techniques de composants électroniques |
|
TCA9617ADGKR Fiches technique(PDF) 7 Page - Texas Instruments |
|
|
TCA9617ADGKR Fiches technique(HTML) 7 Page - Texas Instruments |
7 / 17 page TCA9617A SLAVE 1 MHz Master 1 MHz VCCA VCCB 240 820 2 .5 V 0 .9 V SDAA SCLA EN SCLB SDAB 240 820 BUS A BUS B TCA9617A www.ti.com SCPS244 – JUNE 2013 APPLICATION INFORMATION A typical application is shown in Figure 4. In this example, the system master is running on a 0.9-V I2C bus, and the slave is connected to a 2.5-V bus. Both buses are running at 400 kHz. Decoupling capacitors are required but are not shown in Figure 2 for simplicity. The TCA9617A is 5 V tolerant so no additional circuits is required to translate between 0.8-V to 5.5-V bus voltages and 2.7-V to 5.5-V bus voltages. When the A side of the TCA9617A is pulled low by a driver on the I2C bus, a comparator detects the falling edge when it goes below 0.7 VCCA and cause the internal driver on the B side to turn on. The B-side will first pull-down to 0-V and then settle to 0.5-V. When the B side of the TCA9617A falls below 0.45 V, the TCA9617A will detect the falling edge, turn on the internal driver on the A side and pull the A-side pin down to ground. In order to illustrate what would be seen for an A to B transition refer to Figure 6, and for a B to A transition see Figure 5. On the B-side bus of the TCA9617A, the clock and data lines will have a positive offset from ground equal to the VOL of the TCA9617A. After the eighth clock pulse, the data line is pulled to the VOL of the slave device, which is close to ground in this example. At the end of the acknowledge, the level rises only to the low level set by the driver of the TCA9617A for a short delay (approximately 0.5-V), while the A-side bus rises above 0.3 VCCA and then continues high. Figure 4. Typical Application Diagrams Pull-up Resistor Sizing For the TCA9617A to function correctly, all devices on the B-side must be able to pull the B-side below the voltage input low contention level (0.45-V). This means that the VOL of any device on the B-side must be below 0.4-V to ensure proper operation. The VOL of a device can be adjusted by changing the IOL through the device which is set by the pull-up resistor value. The pull-up resistor on the B-side must be carefully selected to ensure that logic levels will be transferred correctly to the A-side. The B-side pullup resistor sizing must also ensure that the RC is greater than 20 ns. Shorter RCs will increase the pedestal overshoot discussed in the next section. Note that the B-side RC should also be less than 1 µs to conform with the I2C standard mode specification. Copyright © 2013, Texas Instruments Incorporated Submit Documentation Feedback 7 Product Folder Links: TCA9617A |
Numéro de pièce similaire - TCA9617ADGKR |
|
Description similaire - TCA9617ADGKR |
|
|
Lien URL |
Politique de confidentialité |
ALLDATASHEET.FR |
ALLDATASHEET vous a-t-il été utile ? [ DONATE ] |
À propos de Alldatasheet | Publicité | Contactez-nous | Politique de confidentialité | Echange de liens | Fabricants 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 |