Datasheet

UCC27511

UCC27512

www.ti.com

SLUSAW9E –FEBRUARY 2012–REVISED DECEMBER 2013

Low Propagation Delays

The UCC27511 and UCC27512 driver devices feature best-in-class input-to-output propagation delay of 13 ns

(typ) at VDD = 12 V, which promises the lowest level of pulse transmission distortion available from industry-

standard gate-driver devices for high-frequency switching applications. As seen in Figure 14, there is very little

variation of the propagation delay with temperature and supply voltage as well, offering typically less than 20-ns

propagation delays across the entire range of application conditions.

Thermal Information

The useful range of a driver is greatly affected by the drive-power requirements of the load and the thermal

characteristics of the package. In order for a gate driver to be useful over a particular temperature range the

package must allow for the efficient removal of the heat produced while keeping the junction temperature within

rated limits. The thermal metrics for the driver package is summarized in the section of the datasheet. For

detailed information regarding the table, please refer to the Application Note from Texas Instruments entitled IC

Package Thermal Metrics (SPRA953).

The UCC27511 and UCC27512 devices are offered in SOT-23, 6-pin package (DBV) and 3 mm × 3 mm, WSON

6-pin package with exposed thermal pad (DRS), respectively. The thermal information table summarizes the

thermal performance metrics related to the two packages. θ

metric should be used for comparison of power

dissipation between different packages. Under identical power-dissipation conditions, the DRS package will

maintain a lower die temperature than the DBV. The ψ

and ψ

metrics are used when estimating the die

temperature during actual application measurements.

The DRS is a better thermal package overall because it has the exposed thermal pad and is able to sink heat to

the PCB better than the DBV. The thermal pad in DRS package provides designers with an ability to create an

excellent heat removal sub-system from the vicinity of the device, thus helping to maintain a lower junction

temperature. This pad should be soldered to the copper on the printed circuit board directly underneath the

device package. Then a printed circuit board designed with thermal lands and thermal vias completes a very

efficient heat-removal subsystem. In such a design, the heat is extracted from the semiconductor junction

through the thermal pad, which is then efficiently conducted away from the location of the device on the PCB

through the thermal network. This helps to maintain a lower board temperature near the vicinity of the device

leading to an overall lower device-junction temperature.

In comparison, for the DBV package, heat removal occurs primarily through the leads of the device and the PCB

traces connected to the leads.

Note that the exposed pad in DRS package is not directly connected to any leads of the package, but is

electrically and thermally connected to the substrate of the device which is the ground of the device. TI

recommends to externally connect the exposed pads to GND in PCB layout for better EMI immunity.

Product Folder Links: UCC27511 UCC27512