PESD12VL2BT-Q | Dual-channel low-capacitance ESD protection diode

The PESD12VL2BT-Q is a low-capacitance bidirectional ESD protection diode in SOT23 package, designed to protect two signal lines from damage caused by ESD and other transients. It is often used in sensitive digital interfaces to prevent damage from static electricity and surges.

Get to know PESD12VL2BT-Q

Features and benefits

• ESD protection of two lines
• Max. peak pulse power: P_PPM = 200 W
• Low clamping voltage: V_CL = 37 V
• Small SMD plastic package
• Ultra low leakage current: I_RM = 1 nA
• ESD protection up to 30 kV
• IEC 61000-4-2, level 4 (ESD)
• IEC 61000-4-5 (surge); I_PPM = 5 A
• Qualified according to AEC-Q101 and recommended for use in automotive applications

Pinning information

Absolute Maximum Ratings

How to use PESD12VL2BT-Q

The PESD12VL2BT-Q is a dual-channel, bidirectional ESD protection diode array, specifically designed to protect signal lines from being broken by static electricity or transient surges. It operates almost silently and does not affect the signal in normal times. When an incident occurs, it can instantly conduct and discharge the energy.

Normal operating state
When the signal line voltage is within the safe range, the diode is in reverse cutoff, with a very small leakage current, and the impact on the signal is approximately zero.
It can be used in:

• High-speed data lines
• Communication interfaces
• Front-end of MCU/IC's I/O ports

When ESD/ surge occurs
When there is an external static discharge or transient spike:

1. The voltage on the signal line suddenly exceeds the breakdown voltage of the device, and the voltage surges abruptly.
2. When the internal PN junction or avalanche effect occurs, the diode opens within the picosecond to nanosecond range, forming a low-resistance path, and the TVS junction conducts in avalanche mode.
3. The energy is dissipated: The large current is shunted to GND, the signal line voltage is clamped at the safe value, and the subsequent MCU/SOC survives.

Notes：This process is called Voltage Clamping and is the core function of TVS devices.

---

How does the dual-channel work?

• Two signal lines are independently protected
• Share a common grounding terminal

Commonly used in: USB/UART/CAN/GPIO

application example

• Computers and peripherals
• Audio and video equipment
• Cellular handsets and accessories
• Communication systems
• Portable electronics
• SIM card protection

Notes: Under normal circumstances, it rarely participates in circuit operation; when static electricity or transient surges occur, it will conduct rapidly within nanoseconds, clamping and discharging the dangerous energy to the ground, thereby effectively protecting the reliability of the subsequent chips and the system.

---

FAQ about PESD12VL2BT-Q

Q1: Will it affect the normal signal?
No. Within the normal operating voltage range, the device is in the cut-off state and the leakage current is very small, having almost no impact on the signal.
Q2: What is the suitable operating voltage range for PESD12VL2BT-Q?
The rated reverse voltage is approximately 12V, and it is suitable for signal line protection of 12V and below.
Q3: Where should it be placed in the circuit?
It should be placed close to the interface end. Because static electricity is discharged before entering the PCB, it can reduce the surge energy from entering the board.
Q4: Can it be replaced with other SOT-23 ESD diodes?
Consider replacement if the following conditions are the same:

• Similar operating voltage
• Similar capacitance level
• Same pin definition

Before replacement, carefully check Pin Assignment and Clamping Voltage.