TPIC2603

6CHANNEL SERIAL INTERFACE LOW SIDE DRIVER

SLIS056A − FEBRUARY 1995 − REVISED MARCH 1996

11

POST OFFICE BOX 655303

POST OFFICE BOX 1443

PRINCIPLES OF OPERATION

over-temperature sensing

The TPIC2603 monitors the junction temperature of the die to detect over-temperature conditions which may

damage the device. When the junction temperature goes above approximately 170

°C, the fault logic sets the

global over-temperature fault bit. An over-temperature fault is reported using the serial interface on bit 6 (for 8-bit

configuration) or bit 14 (for 16-bit configuration). The global over-temperature fault output in the serial data is

exclusively ORed with the second bit (bit 6 for 8-bit configuration or bit 14 for 16-bit configuration) of data input

to the SDI terminal. Bit 6 or bit 14 of the input data should be set low. Over-temperature faults are for

informational purposes only and do not affect the state of the drains. Figure 8 illustrates device operation under

over-temperature conditions.

160

°C

170

°C

Junction Temperature

Drains (Not Disabled)

Fault Bit

Figure 8. Over-Temperature Sense

PARAMETER MEASUREMENT INFORMATION

OUTPUT CURRENT

vs

TIME FOR INCREASING LOAD RESISTANCE

Region 1

Region 2

t1

t2

First output current pulses after turn-on in chopping mode with

resistive load.

0

3

0

t1 ≈ 55 µs

t2 ≈ 3.5 ms

t -Time

t - Time

REGION 1 CURRENT WAVEFORM

IL

t2

t1

t1

2

1

Region 3

TC = 25°C

NOTES: A. Region 1 − Analog current limit holds the maximum current while the device runs in chop mode.

B. Region 2 − Analog current limit is removed but device continues in chop mode.

C. Region 3 − Current is below chop mode sense; therefore, it is in normal operation. Variable load is resistance over time.

Figure 9. Chopping-Mode Characteristics