Product Descriptions
The LT® 1074 is a 5A (LT1076 is rated at 2A) monolithic bipolar switching regulator which requires only a few external parts for normal operation. The power switch, all oscillator and control circuitry, and all current limit components, are included on the chip. The topology is a classic positive “buck” configuration but several design innovations allow this device to be used as a positive-to-negative converter, a negative boost converter, and as a flyback converter. The switch output is specified to swing 40V below ground, allowing the LT1074 to drive a tappedinductor in the buck mode with output currents up to 10A.
The LT1074 uses a true analog multiplier in the feedback loop. This makes the device respond nearly instantaneously to input voltage fluctuations and makes loop gain independent of input voltage. As a result, dynamic behavior of the regulator is significantly improved over previous designs.
On-chip pulse by pulse current limiting makes the LT1074 nearly bust-proof for output overloads or shorts. The input voltage range as a buck converter is 8V to 60V, but a selfboot feature allows input voltages as low as 5V in the inverting and boost configurations.
The LT1074 is available in low cost TO-220 or TO-3 packages with frequency pre-set at 100kHz and current limit at 6.5A (LT1076 = 2.6A). A 7-pin TO-220 package is also available which allows current limit to be adjusted down to zero. In addition, full micropower shutdown can be programmed. See Application Note 44 for design details.
Product Features
■ 5A Onboard Switch (LT1074)
■ 100kHz Switching Frequency
■ Greatly Improved Dynamic Behavior
■ Available in Low Cost 5 and 7-Lead Packages
■ Only 8.5mA Quiescent Current
■ Programmable Current Limit
■ Operates Up to 60V Input
■ Micropower Shutdown Mode
Product Applications
■ Buck Converter with Output Voltage Range of 2.5V to 50V
■ Tapped-Inductor Buck Converter with 10A Output at 5V
■ Positive-to-Negative Converter
■ Negative Boost Converter
■ Multiple Output Buck Converter
Product Specification
| Attribute | Attribute value |
| ANSM-Part# | ANSM-LT1074CT7 |
| Category | Integrated Circuits (ICs) |
| Power Management (PMIC) | |
| Voltage Regulators - DC DC Switching Regulators | |
| Mfr | - |
| Series | - |
| Packaging | Tube |
| Part Status | Discontinued at DigiKey |
| Function | Step-Up, Step-Down, Step-Up/Step-Down |
| Output Configuration | Positive or Negative |
| Topology | Buck, Boost, Flyback |
| Output Type | Adjustable |
| Number of Outputs | 1 |
| Voltage - Input (Min) | 8V |
| Voltage - Input (Max) | 45V |
| Voltage - Output (Min/Fixed) | 2.5V |
| Voltage - Output (Max) | 35V |
| Current - Output | 5.5A (Switch) |
| Frequency - Switching | 100kHz |
| Synchronous Rectifier | No |
| Mounting Type | Through Hole |
| Package / Case | TO-220-7 Formed Leads |
| Supplier Device Package | TO-220-7 |
| Base Product Number | LT1074 |
Product Photos
For more product information, please download the PDF
