Overview
The TDA3681JR/N2S is a multiple output voltage regulator integrated circuit produced by NXP USA Inc. It is designed for use in automotive applications, particularly in car radios with or without a microcontroller. This IC combines multiple voltage regulators, a power switch, and an ignition buffer, making it a comprehensive solution for managing power in vehicle electronics.
Key Specifications
| Parameter | Conditions | Value | Unit |
|---|---|---|---|
| VP1 Supply Voltage (Operating) | -18 to +50 V | -18 to +50 | V |
| VP1 Supply Voltage (Reverse Polarity Non-Operating) | -18 V | -18 | V |
| VP1 Supply Voltage (Jump Start) | t ≤ 10 minutes | -30 | V |
| VP1 Supply Voltage (Load Dump Protection) | t ≤ 50 ms; tr ≥ 2.5 ms | -50 | V |
| Tamb Ambient Temperature (Operating) | -40 to +85 °C | -40 to +85 | °C |
| Tj Junction Temperature (Operating) | -40 to +150 °C | -40 to +150 | °C |
| Ptot Total Power Dissipation | -62 W | -62 | W |
| Rth(j-c) Thermal Resistance from Junction to Case | 1.3 K/W | 1.3 | K/W |
| Rth(j-a) Thermal Resistance from Junction to Ambient in Free Air | 50 K/W | 50 | K/W |
| Iq Quiescent Current (IREG1 = 600 mA) | -25 to 60 mA | -25 to 60 | mA |
| SVRR Supply Voltage Ripple Rejection (fi = 3 kHz; Vi = 2 V (p-p)) | 60 to 70 dB | 60 to 70 | dB |
| Vdrop(REG1) Drop-out Voltage (IREG1 = 550 mA; VP1 = 8.55 V) | -0.4 to 0.7 V | -0.4 to 0.7 | V |
| Im(REG1) Current Limit (VREG1 > 7 V) | 0.65 to 1.2 A | 0.65 to 1.2 | A |
| Vo(REG2) Output Voltage (0.5 mA ≤ IREG2 ≤ 300 mA) | 4.75 to 5.25 V | 4.75 to 5.25 | V |
| Vo(REG4) Output Voltage (1 mA ≤ IREG4 ≤ 1 A) | 3.14 to 3.46 V | 3.14 to 3.46 | V |
Key Features
- Extremely low noise behavior and good stability with very small output capacitors.
- Four fixed voltage regulators with foldback current protection (regulators 1, 2, 3, and 4).
- Regulator 2 operates during load dump and thermal shutdown, suitable for supplying a microcontroller.
- Regulators 3 and 4 have a second supply pin to reduce power dissipation by connecting to a lower supply voltage (>6.5 V).
- A power switch with protection, operated by a control input.
- Reset and hold outputs for interfacing with a microcontroller.
- Provision for a reserve supply capacitor to maintain energy for regulator 2 during voltage loss.
- Supply voltage range from -18 to +50 V, with load dump protection and negative supply voltage tolerance.
- Low quiescent current in standby mode.
Applications
The TDA3681JR/N2S is primarily designed for use in automotive electronics, particularly in car radios. It is suitable for applications with or without a microcontroller, providing robust power management and protection features necessary for the harsh automotive environment.
- Car radios and infotainment systems.
- Automotive electronic control units (ECUs).
- Other vehicle electronic systems requiring multiple voltage regulation and power switching.
Q & A
- What is the primary function of the TDA3681JR/N2S?
The TDA3681JR/N2S is a multiple output voltage regulator with a power switch and an ignition buffer, designed for use in automotive electronics.
- What is the supply voltage range for the TDA3681JR/N2S?
The supply voltage range is from -18 to +50 V.
- How many voltage regulators does the TDA3681JR/N2S contain?
The IC contains four fixed voltage regulators (regulators 1, 2, 3, and 4).
- What is the purpose of the second supply pin for regulators 3 and 4?
The second supply pin can be connected to a lower supply voltage (>6.5 V) to reduce power dissipation.
- Does the TDA3681JR/N2S have any protection features?
Yes, it includes load dump protection, thermal shutdown protection, and foldback current protection for the regulators.
- Can the TDA3681JR/N2S operate during negative supply voltages?
Yes, it can withstand negative supply voltages and load dump pulses.
- What is the quiescent current in standby mode?
The quiescent current is low in standby mode when regulators 1, 3, and 4 and the power switch are switched off and the ignition input is low.
- Is the TDA3681JR/N2S suitable for use in car radios with microcontrollers?
Yes, it is designed for use in car radios with or without microcontrollers, providing necessary power management and protection features.
- What is the thermal resistance from junction to ambient in free air?
The thermal resistance from junction to ambient in free air is 50 K/W.
- What are the typical output voltages for regulators 2 and 4?
Regulator 2 typically outputs 5 V, and regulator 4 typically outputs 3.3 V.
