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Regulator

1

2

3

5

4

34 VDC

TPS2816

0.1

µF

PWM

Controller

0.1

µF

4.7

µF

Out

GND

0.1

µF

10

µF

+

2.5-V/3.3-V, 3-A Application

TPS2816-EP, TPS2817-EP, TPS2818-EP

TPS2819-EP, TPS2828-EP, TPS2829-EP

SGDS039 – FEBRUARY 2008

external circuitry, providing the power dissipation rating for the driver is not exceeded. When using the on-board

series regulator, an electrolytic output capacitor of 4.7

µF or larger is recommended. Although not required, a

0.1

µF ceramic capacitor on the input of the regulator can help suppress transient currents (see Figure 22).

regulator.

Figure 22. Boost Application

The TPS2816 and TPS2818 drivers include active pullup circuits on the inputs to eliminate the need for external

pullup resistors when using controllers with open-collector outputs (such as the TL5001). The TPS2817 and

TPS2819 drivers have standard CMOS inputs providing a total device operating current of less than 50

µA. All

large amounts of current (Approximately 5 mA) when the inputs are in the range of one-half of the supply

voltage. In normal operation, the driver input is in this range for a very short time. Care should be taken to avoid

use of very low slew-rate inputs, used under normal operating conditions. Although not destructive to the device,

slew rates slower than 0.1 V/

µs are not recommended.

The BiCMOS output stage provides high instantaneous drive current to rapidly toggle the power switch, and very

low drop to each rail to ensure proper operation at voltage extremes.

Low-voltage circuits (less than 14 V) that require very low quiescent currents can use the TPS2828 and

TPS2829 drivers. These drivers use typically 0.2

µA of quiescent current (with inputs high or low). They do not

have the internal regulator or the active pullup circuit, but all other specifications are the same as for the rest of

the family.

Figure 23 illustrates the use of the TPS2817 with a TL5001 PWM controller and a TPS1110 in a simple

step-down converter application. The converter operates at 275 kHz and delivers either 2.5 V or 3.3 V

(determined by the value of R6) at 3 A (5 A peak) from a 5-V supply. The bill of materials is provided in Table 1.

16

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Product Folder Link(s): TPS2816-EP TPS2817-EP TPS2818-EP TPS2819-EP TPS2828-EP TPS2829-EP