Electronic Components Datasheet Search |
|
PT7761A Datasheet(PDF) 7 Page - Texas Instruments |
|
PT7761A Datasheet(HTML) 7 Page - Texas Instruments |
7 / 9 page Application Notes For technical support and more information, see inside back cover or visit www.ti.com Pin-Coded Output Voltage Adjustment of PT7761 “Excalibur™” ISRs The PT7761 Excalibur power module incorporates a pin-coded output voltage control. These regulators in- clude five control pins, identified VID0–VID4 (pins 1–5) respectively. By selectively grounding VID0-VID4, the output voltage of this regulator can be programmed in incremental steps over the output voltage range, 1.3V to 3.5V. The program code and voltage range is designed to be compatible with the “Voltage ID” specification defined for popular microprocessors. Refer to Figure 1 for the connection schematic, and the applicable data sheet for the program code. Notes: 1. The programming convention is as follows:- Logic 0: Connect to pin15 (Remote Sense Ground). Logic 1: Open circuit/open drain (See notes 2, & 4) 2. Do not connect pull-up resistors to the voltage programming pins. 3. Use pin 15 (Rem Sense Gnd) as the logic “0” reference. While the regular ground (pins 16–22) can also be used for programming, doing so will degrade the load regulation of the product. If the remote sense ground is not used, pin 15 must be connected to pin 16 for optimum output voltage accuracy. Figure 1 4. If active devices are used to ground the voltage control pins, low-level open drain MOSFET devices should be used over bipolar transistors. The inherent Vce(sat) in bipolar devices introduces errors in the device’s internal voltage control circuit. Discrete transistors such as the BSS138, 2N7002, IRLML2402, are examples of appropriate devices. Active Voltage Programming: Special precautions should be taken when making changes to the voltage control progam code while the unit is powered. It is highly recommended that the ISR be either powered down or held in standby. Changes made to the program code while Vout is enabled induces high current transients through the device. This is the result of the electrolytic output capacitors being either charged or dis- charged to the new output voltage set-point. The transient current can be minimized by making only incremental changes to the binary code, i.e. one LSB at a time. A minimum of 100µs settling time between each program state is also recommended. Making non-incremental changes to VID3 and VID4 with the output enabled is discouraged. If they are changed, the transients induced can overstress the device. If the program code cannot be asserted prior to power-up, pull pin 6 (STBY) to GND during the period that the input voltage is applied. The release of pin 6 will then to allow the device to initiate a soft-start power-up to the program voltage. PT7761 C out + C in + 1 µH (Optional) +5V COM STBY L O A D PT7761 432 1 3 1 23 – 30 15 61 6 – 22 9 – 14 5 7 S y n c GND Sns ( + ) Sns ( – ) V OUT V IN Stb y VID0 - VID4 |
Similar Part No. - PT7761A |
|
Similar Description - PT7761A |
|
|
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 |