MAX5974DETE+T Switching Controllers Active-Clamped, Spread-Spectrum, Current-Mode PWM Controllers
♠ Product Description
| Product Attribute | Attribute Value |
| Manufacturer: | Maxim Integrated |
| Product Category: | Switching Controllers |
| RoHS: | Details |
| Topology: | - |
| Number of Outputs: | 1 Output |
| Switching Frequency: | 600 kHz |
| Duty Cycle - Max: | 82 % |
| Input Voltage: | 10.5 V |
| Output Voltage: | - |
| Output Current: | 1 mA |
| Minimum Operating Temperature: | - 40 C |
| Maximum Operating Temperature: | + 85 C |
| Mounting Style: | SMD/SMT |
| Package / Case: | TQFN-16 |
| Packaging: | Reel |
| Packaging: | Cut Tape |
| Packaging: | MouseReel |
| Brand: | Maxim Integrated |
| Fall Time: | 14 ns |
| Operating Supply Current: | 1.8 mA |
| Operating Supply Voltage: | 12 V to 21 V |
| Product Type: | Switching Controllers |
| Rise Time: | 27 ns |
| Series: | MAX5974 |
| Factory Pack Quantity: | 2500 |
| Subcategory: | PMIC - Power Management ICs |
| Type: | Current Mode PWM Controllers |
| Part # Aliases: | MAX5974 |
♠Active-Clamped, Spread-Spectrum, Current-Mode PWM Controllers
The MAX5974_ provide control for wide-input-voltage, active-clamped, current-mode PWM, forward converters in Power-over-Ethernet (PoE) powered device (PD) applications. The MAX5974A/MAX5974C are well-suited for universal or telecom input range, while the MAX5974B/ MAX5974D also accommodate low input voltage down to 10.5V.
The devices include several features to enhance supply efficiency. The AUX driver recycles magnetizing current instead of wasting it in a dissipative clamp circuit. Programmable dead time between the AUX and main driver allows for zero-voltage switching (ZVS). Under light-load conditions, the devices reduce the switching frequency (frequency foldback) to reduce switching losses.
The MAX5974A/MAX5974B feature unique circuitry to achieve output regulation without using an optocoupler, while the MAX5974C/MAX5974D utilize the traditional optocoupler feedback method. An internal error amplifier with a 1% reference is very useful in nonisolated design, eliminating the need for an external shunt regulator.
The devices feature a unique feed-forward maximum duty-cycle clamp that makes the maximum clamp voltage during transient conditions independent of the line voltage, allowing the use of a power MOSFET with lower breakdown voltage. The programmable frequency dithering feature provides low-EMI, spread-spectrum operation.
The MAX5974_ are available in 16-pin TQFN-EP packages and are rated for operation over the -40°C to +85°C and -40°C to +125°C temperature ranges.
● Peak Current-Mode Control, Active-Clamped Forward PWM Controller
● Regulation Without Optocoupler (MAX5974A/ MAX5974B)
● Internal 1% Error Amplifier
● 100kHz to 600kHz Programmable ±8% Switching Frequency, Synchronization Up to 1.2MHz
● Programmable Frequency Dithering for Low-EMI, Spread-Spectrum Operation
● Programmable Dead Time, PWM Soft-Start, Current Slope Compensation
● Programmable Feed-Forward Maximum Duty-Cycle Clamp, 80% Maximum Limit
● Frequency Foldback for High-Efficiency Light-Load Operation
● Internal Bootstrap UVLO with Large Hysteresis
● 100μA (typ) Startup Supply Current
● Fast Cycle-by-Cycle Peak Current-Limit, 35ns Typical Propagation Delay
● 115ns Current-Sense Internal Leading-Edge Blanking
● Output Short-Circuit Protection with Hiccup Mode
● Reverse Current Limit to Prevent Transformer Saturation Due to Reverse Current
● Internal 18V Zener Clamp on Supply Input
● 3mm x 3mm, Lead-Free, 16-Pin TQFN-EP
● PoE IEEE® 802.3af/at Powered Devices
● High-Power PD (Beyond the 802.3af/at Standard)
● Active-Clamped Forward DC-DC Converters
● IP Phones
● Wireless Access Nodes
● Security Cameras
