Electronic Components Datasheet Search |
|
SN65HVD61 Datasheet(PDF) 11 Page - Texas Instruments |
|
|
SN65HVD61 Datasheet(HTML) 11 Page - Texas Instruments |
11 / 20 page SN65HVD61 www.ti.com SLLS770D – JANUARY 2007 – REVISED JUNE 2011 APPLICATION INFORMATION THERMAL SHUTDOWN In most cases, the device ’s internal junction temperature will not reach the thermal shutdown temperature if operated within the recommended operating conditions. However, during fault conditions, such as driver short-circuit, the junction temperature may reach the thermal shutdown limit. This also depends on the thermal characteristics of the device mounting, the circuit board, and environmental factors. After the device reaches the thermal shutdown temperature, the driver outputs will be disabled, and the device will cool down. If the short-circuit is still present when the drivers are re-enabled, this thermal shutdown cycle will repeat until the short-circuit fault is removed. For long-term reliability, the package power dissipation must not exceed the values in the data sheet POWER DISSIPATION RATINGS for extended periods. POWER-UP TRANSIENTS The absolute maximum ratings for Vcc and Vdd specify the limits for these supplies. During initial power-on, these supply voltages may instantaneously drop below the given lower limit. Designers should consider that diodes in the circuitry will begin to turn on if the voltage becomes too negative, and that damage may occur if these diodes dissipate significant power internal to the device. The actual threshold for possible damage is a function of both undervoltage magnitude and undervoltage transient duration. Further, the allowable undervoltage transient conditions depend on factors such as device junction temperature and power supply source impedance. THERMAL CHARACTERISTICS OF IC PACKAGES Junction-to-Ambient Thermal Resistance ( θJA) is defined as the difference in junction temperature to ambient temperature divided by the operating power. θJA is NOT a constant and is a strong function of • the PCB design (50% variation) • altitude (20% variation) • device power (5% variation) θJA can be used to compare the thermal performance of packages if the specific test conditions are defined and used. Standardized testing includes specification of PCB construction, test chamber volume, sensor locations, and the thermal characteristics of holding fixtures. θJA is often misused when it is used to calculate junction temperatures for other installations. TI uses two test PCBs as defined by JEDEC specifications. The low-k board gives average in-use condition thermal performance and consists of a single trace layer 25 mm long and 2-oz thick copper. The high-k board gives best case in-use condition and consists of 2 1-oz buried power planes with a single trace layer 25 mm long with 2-oz thick copper. A 4% to 50% difference in θJA can be measured between these two test cards Junction-to-case thermal resistance ( θJC) is defined as difference in junction temperature to case divided by the operating power. It is measured by putting the mounted package up against a copper block cold plate to force heat to flow from die, through the mold compound into the copper block. θJC is a useful thermal characteristic when a heatsink is applied to package. It is NOT a useful characteristic to predict junction temperature as it provides pessimistic numbers if the case temperature is measured in a non-standard system and junction temperatures are backed out. It can be used with θJB in 1-dimensional thermal simulation of a package system. Junction-to-board thermal resistance ( θJB ) is defined to be the difference in the junction temperature and the PCB temperature at the center of the package (closest to the die) when the PCB is clamped in a cold −plate structure. θJB is only defined for the high-k test card. Copyright © 2007–2011, Texas Instruments Incorporated 11 |
Similar Part No. - SN65HVD61 |
|
Similar Description - SN65HVD61 |
|
|
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 |