點晶科技股份有限公司

SILICON TOUCH TECHNOLOGY INC.

DM164

8x3-CHANNEL CONSTANT CURRENT LED DRIVERS

Version:A.002

Page 12

MSEL

DIN

GD[383]a

DCK

(DCKPH=L)

DOUT

(DOUTPH=L)

DOUT

(DOUTPH=H)

LTH

12

192

D&G

mode

GD mode

D&G[0]

384

1

384

2

DCK

(DCKPH=H)

12

192

384

1

384

2

10 GCK Latencies

GD[382]a

GD[0]a

GD[383]a

ER[383]a

ER[382]a

ER[381]a

GD[383]b

GD[382]b

GD[0]b

GD[383]a

ER[383]a

ER[382]a

ER[0]a

ER[0]a

Figure 4. GD Mode Data Input Timing Chart

Thermal Alarm and Shutdown

The DM164 provides a temperature error detection circuit, when EN_B=H and the junction

temperature of the IC reaches about 130

low level. At this moment, the system should start up the fan or decrease the output

currents to lower the junction temperature. If the system has not any protected circuit, the

junction temperature might continue to rise. Once it reaches approximately above 170

T170 signal and a Shutdown signal will cause the driver to shutdown all the outputs, the

ALARM pin remains in low level. Basically, the IC will cool down and return to the safe

operating temperature approximately below 130

130

outputs. Operation in the thermal situation for a long time may cause chip damage

permanently. The thermal error signals (T130, T170, Shutdown) can be transferred out

from DOUT pin.

Normal

Alarm

Normal

Normal

Normal

Alarm

Alarm + Shutdowm

130 C

170 C

T130 =“H＂

T170 =“L＂

T130 =“L＂

T170 =“L＂

T130 =“H＂

T170 =“H＂

Figure 5. Thermal Alarm and Shutdown