 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
ISL54206A Datasheet(PDF) 11 Page - Intersil Corporation |
|
||||||||||||||||||||||||||||||
ISL54206A Datasheet(HTML) 11 Page - Intersil Corporation |
|
|
11 / 19 page  ISL54206A 11 FN6515.2 September 30, 2010 LOGIC CONTROL The state of the ISL54206A device is determined by the voltage at the IN pin (pin 2) and the CTRL pin (pin 10). Refer to “Truth Table” on page 2. These logic pins are 1.8V logic compatible when VDD is in the range of 2.7V to 3.6V and can be controlled by a standard µprocessor. The CTRL pin is internally pulled low through a 4MΩ resistor to ground and can be left floating or tri-stated by the µprocessor. The CTRL control pin is only active when IN is logic “0”. The IN pin does not have an internal pull-down resistor and must not be allowed to float. It must be driven High or Low. The voltage at the IN pin can exceed the VDD voltage by as much as 2.55V. This allows the VBUS voltage from a computer or USB hub (4.4V to 5.25V) to drive the IN pin while the VDD voltage is in the range of 2.7V to 3.6V. An external pull-down resistor is required from the IN pin to ground when directly driving the IN pin with the computer VBUS voltage. See “USING THE COMPUTER VBUS VOLTAGE TO DRIVE THE “IN” PIN” on page 11. Logic Control Voltage Levels IN = Logic “0” (Low) when IN ≤0.5V IN = Logic “1” (High) when IN ≥1.4V CTRL = Logic “0” (Low) when ≤0.5V or floating. CTRL = Logic “1” (High) when ≥1.4V Audio Mode If the IN pin = Logic “0” and CTRL pin = Logic “1,” the part will be in the Audio mode. In Audio mode, the L (left) and R (right) 3Ω audio switches are ON and the D- and D+ 5Ω USB switches are OFF (high impedance). When nothing is plugged into the common connector or a headphone is plugged into the common connector, the µprocessor will sense that there is no voltage at the VBUS pin of the connector and will drive and hold the IN control pin of the ISL54206A low. As long as the CTRL = Logic “1,” the ISL54206A part will be in the audio mode and the audio drivers of the media player can drive the headphones and play music. USB Mode If the IN pin = Logic “1” and CTRL pin = Logic “0” or Logic “1” the part will go into USB mode. In USB mode, the D- and D+ 5Ω switches are ON and the L and R 3Ω audio switches are OFF (high impedance). When a USB cable from a computer or USB hub is connected at the common connector, the µprocessor will sense the presence of the 5V VBUS and drive the IN pin voltage high. The ISL54206A part will go into the USB mode. In USB mode, the computer or USB hub transceiver and the MP3 player or cell phone USB transceiver are connected and digital data will be able to be transmitted back and forth. When the USB cable is disconnected, the µprocessor will sense that the 5V VBUS voltage is no longer connected and will drive the IN pin low and put the part back into the Audio or Low Power Mode. Low Power Mode If the IN pin = Logic “0” and CTRL pin = Logic “0,” the part will be in the Low Power mode. In the Low Power mode, the audio switches and the USB switches are OFF (high impedance). In this state, the device draws typically 1nA of current. USING THE COMPUTER VBUS VOLTAGE TO DRIVE THE “IN” PIN External IN Pull-Down Resistor Rather than using a microprocessor to control the IN logic pin you can directly drive the IN pin using the VBUS voltage from the computer or USB hub. In order to do this, you must connect an external resistor from the IN pin to ground. When a headphone or nothing is connected at the common connector, the external pull-down will pull the IN pin low putting the ISL54206A in the Audio mode or Low Power mode depending on the condition of the CTRL pin. When a USB cable is connected at the common connector, the voltage at the IN pin will be driven to 5V and the part will automatically go into the USB mode. When the USB cable is disconnected from the common connector, the voltage at the IN pin will be pulled low by the pull-down resistor and return to the Audio Mode or Low Power Mode depending on the condition of the CTRL pin. Note: The voltage at the IN pin can exceed the VDD voltage by as much as 2.55V. This allows the VBUS voltage from a computer or USB hub (4.4V to 5.25V) to drive the IN pin while the VDD voltage is in the range of 2.7V to 3.6V. External IN Series Resistor The ISL54206A contains a clamp circuit between IN and VDD. Whenever the IN voltage is greater than the VDD voltage by more than 2.55V, current will flow through this clamp circuitry into the VDD power supply bus. During normal USB operation, VDD is in the range of 2.7V to 3.6V and IN (VBUS voltage from computer or USB hub) is in the range of 4.4V to 5.25V, the clamp circuit is not active and no current will flow through the clamp into the VDD supply. In a USB application, the situation can exist where the VBUS voltage from the computer could be applied at the IN pin before the VDD voltage is up to its normal operating voltage range and current will flow through the clamp into the VDD power supply bus. This current could be quite high when VDD is OFF or at 0V and could potentially damage other components connected in the circuit. In the application circuit, a 22kΩ resistor has been put in series with the IN pin to limit the current to a safe level during this situation. |
Similar Part No. - ISL54206A |
|
Similar Description - ISL54206A |
|
|
|
Link URL |
| Privacy Policy |
| ALLDATASHEET.NET |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | 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
