Datasheet

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   
  
SLVS196C − JANUARY1999 − REVISED JANUARY 2001
4
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
detailed description (continued)
SYNC
†
The SYNC terminal controls whether the drivers operate in synchronous or nonsynchronous mode. In
synchronous mode, the low-side FET is operated as a synchronous rectifier. In nonsynchronous mode, the
low-side FET is always off.
CROWBAR
†
The CROWBAR terminal overrides the normal operation of the driver. When the CROWBAR terminal is low,
the low-side FET turns on to act as a clamp, protecting the output voltage of the dc/dc converter against over
voltages due to a short across the high-side FET. V
IN
should be fused to protect the low-side FET.
absolute maximum ratings over operating free-air temperature (unless otherwise noted)
†
Supply voltage range, V
CC
(see Note 1) −0.3 V to 16 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input voltage range:BOOT to PGND (high-side driver ON) −0.3 V to 30 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
BOOTLO to PGND −0.3 V to 16 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
BOOT to BOOTLO −0.3 V to 16 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ENABLE, SYNC, and CROWBAR (see Note 2) −0.3 V to 16 V. . . . . . . . . . . . . . . . . . . . .
IN (see Note 2) −0.3 V to 16 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DT (see Note 2) −0.3 V to 30 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Continuous total power dissipation See Dissipation Rating Table. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operating virtual junction temperature range, T
J
−40°C to 125°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage temperature range, T
stg
−65°C to 150°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lead temperature soldering 1,6 mm (1/16 inch) from case for 10 seconds 260°C. . . . . . . . . . . . . . . . . . . . . . .
‡
Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTES: 1. Unless otherwise specified, all voltages are with respect to PGND.
2. High-level input voltages on the ENABLE, SYNC, CROWBAR, IN, and DT terminals must be greater than or equal to 0.7V
CC
.
DISSIPATION RATING TABLE
PACKAGE
T
A
≤ 25°C DERATING FACTOR T
A
= 70°C T
A
= 85°C
PWP with solder
§
2668 26.68 mW/°C 1467 1067
PWP without solder
§
1024 10.24 mW/°C 563 409
D 749 7.49 mW/°C 412 300
JUNCTION-CASE THERMAL RESISTANCE TABLE
PWP Junction-case thermal resistance 2.07 °C/W
§
Test Board Conditions:
1. Thickness: 0.062I
2. 3I × 3I (for packages <27 mm long)
3. 4I × 4I (for packages >27 mm long)
4. 2 oz copper traces located on the top of the board (0.071 mm thick)
5. Copper areas located on the top and bottom of the PCB for soldering
6. Power and ground planes, 1 oz copper (0.036 mm thick)
7. Thermal vias, 0.33 mm diameter, 1.5 mm pitch
8. Thermal isolation of power plane
For more information, refer to TI technical brief, literature number SLMA002.
†
High-level input voltages on ENABLE, SYNC, CROWBAR, IN, and DT must be greater than or equal to 0.7V
CC
.