Overview
The LM337D2T is an adjustable 3-terminal negative voltage regulator produced by ON Semiconductor. It is capable of supplying in excess of 1.5 A over an output voltage range of −1.2 V to −37 V. This regulator is known for its ease of use, requiring only two external resistors to set the output voltage. It features internal current limiting, thermal shutdown, and safe area compensation, making it highly reliable and essentially blow-out proof.
Key Specifications
| Parameter | Symbol | Value | Unit |
|---|---|---|---|
| Input-Output Voltage Differential | VI−VO | 40 | Vdc |
| Output Current | IO | 1.5 | A |
| Power Dissipation | PD | Internally Limited | W |
| Thermal Resistance, Junction-to-Ambient | θJA | 5.0 (Case 221A), 70 (Case 936) | °C/W |
| Thermal Resistance, Junction-to-Case | θJC | 4.0 (Case 221A), 3.0 (Case 936) | °C/W |
| Operating Junction Temperature Range | TJ | −40 to +125 | °C |
| Storage Temperature Range | Tstg | −65 to +150 | °C |
| Reference Voltage | VREF | −1.25 | V |
| Line Regulation | KVI | 0.01 to 0.04 %/V | |
| Load Regulation | KVO | 0.3 to 1 % | |
| Ripple Rejection | RVF | 60 to 77 dB |
Key Features
- Output current in excess of 1.5 A
- Output voltage adjustable between −1.2 V and −37 V
- Internal thermal overload protection
- Internal short circuit current limiting constant with temperature
- Output transistor safe-area compensation
- Excellent thermal regulation: 0.002%/V
- 50 ppm/°C temperature coefficient
- High ripple rejection: up to 77 dB
- Standard 3-lead transistor packages
Applications
The LM337D2T is versatile and can be used in a variety of applications, including local, on-card regulation. It can be configured as a programmable output regulator or as a precision current regulator by connecting a fixed resistor between the adjustment and output terminals. It is suitable for applications requiring adjustable negative voltage regulation with high reliability and performance.
Q & A
- What is the output voltage range of the LM337D2T?
The LM337D2T has an output voltage range of −1.2 V to −37 V. - How much current can the LM337D2T supply?
The LM337D2T can supply in excess of 1.5 A. - What are the key protection features of the LM337D2T?
The LM337D2T features internal thermal overload protection, short circuit current limiting, and safe area compensation. - How do I set the output voltage of the LM337D2T?
The output voltage is set using two external resistors connected to the adjustment terminal. - What is the thermal resistance of the LM337D2T?
The thermal resistance (θJA) is 5.0 °C/W for Case 221A and 70 °C/W for Case 936, and the thermal resistance (θJC) is 4.0 °C/W for Case 221A and 3.0 °C/W for Case 936. - What is the operating junction temperature range of the LM337D2T?
The operating junction temperature range is −40 to +125 °C. - How does the LM337D2T handle ripple rejection?
The LM337D2T has high ripple rejection, up to 77 dB, which can be further improved by bypassing the adjustment terminal with a capacitor. - Can the LM337D2T be used as a current regulator?
Yes, the LM337D2T can be used as a precision current regulator by connecting a fixed resistor between the adjustment and output terminals. - What are the storage temperature limits for the LM337D2T?
The storage temperature range is −65 to +150 °C. - What is the reference voltage of the LM337D2T?
The reference voltage (VREF) is typically −1.25 V.
