CLT3-4B Datasheet, PDF (9/13 Pages) STMicroelectronics – Current limited over-voltage protected quad digital termination

CLT3-4B
Application information
Figure 10. Current sharing in the CLT device when IN₄ is biased at - 30 V and the
others at + 30 V, R_I = 1.8 kΩ
Vcc = + 30 V
4.7 k Ω
0.8 mA
V_C
I₁ = + 30 V
IN_N
3.7 mA
1.8 kΩ
V_CL= 38 V
I_{REG N}
GND (0 V)
COM
I₂ = -30 V
1.8 kΩ
16.2 mA
IN₄
I_REG4
CLT3 - 4
OUT₁
OPTO_N
OPTO₄
OUT₂
Figure 11. TSSOP20 printed circuit board example
MODULE
CONNECTOR
GND
COMMON PAD
COM
IN₁
ESD₁₂
IN₂
V_C
ESD_C
IN₃
ESD₃₄
IN₄
COM
COOLING PAD
COM
OUT₁
COM₁₂
OUT₂
COM
COM
OUT₃
COM₃₄
OUT₄
COM
The input and supply pins are designed to withstand electromagnetic interferences. As
shown on the device block diagram, each channel input is protected by a clamping diode
that is connected to the common pin COM. Combined with a serial input resistance
R_I = 1.2 kΩ, this clamping diode implements an effective protection against transient voltage
burst (± 4 kV, IEC 61000-4-4) and voltage surge (± 1 kV, IEC 61000-4-5).
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