Analog Integrated Circuit Device Data

8

Freescale Semiconductor

34932

ELECTRICAL CHARACTERISTICS

DYNAMIC ELECTRICAL CHARACTERISTICS

DYNAMIC ELECTRICAL CHARACTERISTICS

Table 4. Dynamic Electrical Characteristics

Characteristics noted under conditions 5.0 V

Characteristic

Symbol

Min

Typ

Max

Unit

TIMING CHARACTERISTICS

PWM Frequency(20)

–

–

11

kHz

Maximum Switching Frequency During Current Limit Regulation(21)

–

–

20

kHz

Output ON Delay(22)

–

–

18

μs

Output OFF Delay(22)

–

–

12

μs

15

20.5

32

μs

12

16.5

27

μs

Disable Delay Time(26)

–

–

8.0

μs

Output Rise and Fall Time(27)

1.5

3.0

8.0

μs

Short-circuit/Overtemperature Turn-OFF (Latch-OFF) Time(28), (29)

–

–

8.0

μs

Power-ON Delay Time(29)

–

1.0

5.0

ms

Output MOSFET Body Diode Reverse Recovery Time(29)

75

100

150

ns

Charge Pump Operating Frequency(29)

–

7.0

–

MHz

Notes

20.

The maximum PWM frequency should be limited to frequencies < 11 kHz in order to allow the internal high side driver circuitry time to

fully enhance the high side MOSFETs at a duty cycle range of 15 to 85%.

21.

The internal current limit circuitry produces a constant-OFF-time Pulse Width Modulation of the output current. The output load’s

inductance, capacitance, and resistance characteristics affect the total switching period (OFF-time + ON-time), and thus the PWM

frequency during current limit.

22.

* Output Delay is the time duration from 1.5 V on the IN1 or IN2 input signal to the 20% or 80% point (dependent on the transition direction)

of the OUT1 or OUT2 signal. If the output is transitioning HIGH-to-LOW, the delay is from 1.5 V on the input signal to the 80% point of

the output response signal. If the output is transitioning LOW-to-HIGH, the delay is from 1.5 V on the input signal to the 20% point of the

output response signal. See Figure 4, page 9.

23.

The time during which the internal constant-OFF time PWM current regulation circuit has tri-stated the output bridge.

24.

The time during which the current regulation threshold is ignored so the short-circuit detection threshold comparators may have time to

act.

25.

Parameter guaranteed by characterization.

26.

* Disable Delay Time measurement is defined in Figure 5, page 9.

27.

28.

and causing the shutdown circuitry to force the output into an immediate tri-state latch-OFF (see Figure 8). Operation in Current Limit

mode may cause junction temperatures to rise. Junction temperatures above ~160

back”, or decrease, until ~175

region is limited to non-repetitive transient events of duration not to exceed 30 seconds (see Figure 9).

29.

Parameter is Guaranteed By Design.