UC2825DWTR - 1A, 30V High-Speed PWM Controller | Texas Instruments
料号： UC2825DWTR ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $5.4 | $5.40 |
| 10 | $4.85 | $48.50 |
| 100 | $3.81 | $381.00 |
| 500 | $3.35 | $1,675.00 |
| 1,000 | $2.97 | $2,970.00 |
UC2825DWTR 概述
A PWM controller (Pulse-Width Modulation controller) is a semiconductor device that regulates power converter switching by modulating the duty cycle of the driver output stage. PWM controllers belong to the hierarchy: PWM controller -> switching controller -> DC-DC controller -> power management IC -> semiconductor. Compared with simple voltage regulators, PWM controllers provide the high-side/low-side gate drive, current sensing, and protection logic needed to build discrete switching converters.
Key features of the UC2825DWTR include a 1V-threshold current-limit comparator, a TTL-compatible shutdown pin, a soft-start pin that doubles as a maximum duty-cycle clamp (programmable to 80%), and an under-voltage lockout with 800 mV of hysteresis. The output stage delivers ±1.5 A peak totem-pole drive, fully latched logic prevents multiple output pulses, and an internal 5.1V reference powers the control loop.
Architecturally, the UC2825 uses a bipolar process with a double-ended push-pull output stage. The high peak drive current and 30V rating allow direct gate drive of power MOSFETs or small IGBTs in high-frequency SMPS designs. The fully-latched comparator logic eliminates jitter and double-pulsing that can occur in edge-triggered designs, producing clean gate waveforms at high frequency.
Typical applications include telecom and server DC-DC converters, isolated bus converters using push-pull or bridge topologies, industrial power supplies, motor drivers, and high-frequency SMPS modules. The wide input range and high peak drive current make it well suited to 48V telecom rails, industrial 24V systems, and automotive-grade variants exist as UC2825-Q1.
When designing with this device, choose external R/C timing values for the oscillator to set frequency and maximum duty cycle. Use Kelvin connections to the current-sense resistor for accurate 1V-threshold current limiting, and place bypass capacitors close to VCC and the 5.1V reference pin to maintain stability.
This page synthesizes distributor pricing, drop-in compatible alternatives, and practical design notes not found in the manufacturer datasheet alone.
直接替换替代料： UC2825DWTR ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
快速对比工具——选择替代料号进行并排对比：
UC2825DW
✅ 直接替换📋 参考替代料（不在目录中）
UC2825Q1DWTR
✅ 直接替换📋 参考替代料（不在目录中）
UC3825DW
✅ 直接替换📋 参考替代料（不在目录中）
UC3825ADWTR
✅ 直接替换📋 参考替代料（不在目录中）
UC3825BDW
✅ 直接替换📋 参考替代料（不在目录中）
SG2525DW
✅ 直接替换📋 参考替代料（不在目录中）
SG3525DW
✅ 直接替换📋 参考替代料（不在目录中）
UC2825DWTR 最大额定值与电气特性
| Topology Supported | Boost, Flyback, Forward, Full-Bridge, Half-Bridge, Push-Pull |
| 输出类型 | Transistor Driver (PWM) |
| 输出配置 | Positive (Step-Up, Step-Up/Step-Down) |
| Supply Voltage (VCC) | 10 V to 30 V |
| UVLO Thresholds | 9.2 V on / 8.4 V off (800 mV hysteresis) |
| Switching Frequency (max) | 1 MHz |
| Output Current (peak) | 1 A source / 2 A sink (per datasheet 1.5 A typ) |
| Maximum Duty Cycle | 80% (clamped via clamp pin) |
| Current Limit Threshold | 1 V |
| Soft Start Pin | Yes (also functions as max duty cycle clamp) |
| Shutdown Pin | Yes (TTL compatible) |
| Internal Reference | 5.1 V |
| 工作温度 | -40 C to +85 C |
| 封装 | 16-SOIC (DW) |
| 安装类型 | Surface Mount |
UC2825DWTR 引脚配置
| 引脚 1 | INV — Inverting input of error amplifier |
| 引脚 2 | NI — Non-inverting input of error amplifier |
| 引脚 3 | EAOUT — Error amplifier output / compensation |
| 引脚 4 | CLK — Oscillator clock output (for sync) |
| 引脚 5 | RT — Oscillator timing resistor |
| 引脚 6 | CT — Oscillator timing capacitor |
| 引脚 7 | RAMP — Ramp input for PWM comparator |
| 引脚 8 | SS — Soft-start / max duty cycle clamp |
| 引脚 9 | ILIM — Current limit threshold (1V) input |
| 引脚 10 | GND — Ground |
| 引脚 11 | OUTA — Output A (totem-pole) |
| 引脚 12 | OUTB — Output B (totem-pole) |
| 引脚 13 | VCC — Power supply (10V-30V) |
| 引脚 14 | REF — 5.1V internal reference |
| 引脚 15 | SD — Shutdown (TTL compatible) |
| 引脚 16 | VREF — Reference bypass |
典型应用
UC2825DWTR 适用于 6 应用s: Telecom DC-DC Converter Module, Push-Pull Isolated Bus Converter, Industrial 24V SMPS Power Supply, High-Frequency Forward Converter, Automotive DC-DC Converter, Motor Drive Auxiliary Supply.
Telecom DC-DC Converter Module
The UC2825DWTR's 30V rating, 1MHz capability, and 1A peak output drive make it ideal for telecom 48V-bus DC-DC converter modules. Placed as the primary-side controller in half-bridge or full-bridge topologies, the UC2825 directly drives the primary-side MOSFETs without external gate-driver buffers. The 9.2V/8.4V UVLO with 800 mV hysteresis ensures clean start-up and brownout recovery in 36V-72V telecom input ranges, while the 1V-threshold current-limit comparator provides cycle-by-cycle protection during overload events.
推荐
Push-Pull Isolated Bus Converter
The UC2825DWTR's complementary double-ended output stage is optimized for push-pull isolated converters used in industrial 24V and 48V bus applications. Its 1A peak gate drive directly switches the primary MOSFETs of the push-pull stage at frequencies up to 1 MHz, enabling compact magnetic designs and reducing transformer size by 4x versus 250 kHz designs. The 80% maximum duty cycle clamp via the clamp pin prevents transformer core saturation in push-pull topologies where duty-cycle asymmetry could otherwise cause flux imbalance.
推荐
Industrial 24V SMPS Power Supply
The UC2825DWTR operates from 10V to 30V and is well matched to 24V industrial supply rails used in factory automation, PLCs, and motor drives. Its 9.2V/8.4V UVLO accommodates 24V industrial input voltage transients while preventing start-up below the regulation threshold. The internal 5.1V reference, soft-start, and shutdown pins support standard industrial SMPS control loops, and the -40C to +85C temperature range covers factory floor and outdoor enclosure environments.
推荐
High-Frequency Forward Converter
The UC2825DWTR's 1 MHz switching capability and 30V rating enable compact forward converter SMPS designs. Its fully-latched PWM logic eliminates the multiple-pulse risk that affects edge-triggered controllers, producing stable gate waveforms at high frequency. The 80% duty cycle clamp is well suited to single-switch forward converters where duty cycle must remain below 50% to allow transformer reset, while the 1V current limit threshold enables precise peak-current-mode control of the primary switch.
推荐
Automotive DC-DC Converter
The UC2825Q1 variant of this part is AEC-Q100 qualified for automotive applications including 12V and 24V automotive DC-DC converters, EV auxiliary power supplies, and body electronics modules. The Q1 part shares the same 16-SOIC (DW) footprint as the standard UC2825DWTR, enabling PCB layout reuse between commercial and automotive product variants. The 30V rating tolerates 24V automotive load-dump transients, and the wide -40C to +125C temperature range covers automotive under-hood and cabin environments.
推荐
Motor Drive Auxiliary Supply
The UC2825DWTR's totem-pole output stage and 1A peak gate drive make it suitable for auxiliary SMPS in variable-frequency motor drives, where isolated control power must be derived from the DC bus. Its 30V rating covers 24V and 36V industrial bus rails, while the 1 MHz switching capability enables small magnetic components that fit within motor-drive PCB area constraints. The 80% duty cycle clamp and 1V current limit provide robust protection during motor-drive inrush events.
推荐
推荐产品汇总
工程参考数据： UC2825DWTR ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | UC2825DW | UC2825Q1DWTR | UC3825DW | UC3825ADWTR | SG2525DW |
|---|---|---|---|---|---|---|
| Package | 16-SOIC (DW) | 16-SOIC (DW) - same | 16-SOIC (DW) - same | 16-SOIC (DW) - same | 16-SOIC (DW) - same | 16-SOIC (DW) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Microchip Technology |
| UVLO Thresholds | 9.2 V / 8.4 V | 16 V / 9 V | 16 V / 10 V | 8 V / 8 V | ||
| Maximum Duty Cycle | 80% | 100% | 100% | 100% | ||
| Output Current (peak) | 1 A (typ 1.5 A source) | 1 A (typ 1.5 A source) | 1 A (typ 1.5 A source) | 0.5 A | ||
| Supply Voltage (VCC) | 10 V to 30 V | 10 V to 30 V | 10 V to 30 V | 8 V to 35 V | ||
| Switching Frequency (max) | 1 MHz | 1 MHz | 1 MHz | 400 kHz | ||
| Automotive Grade (AEC-Q100) | No | Yes (Q1 suffix) | No | No | ||
| Operating Temperature | -40 C to +85 C | -40 C to +125 C | 0 C to +70 C | -25 C to +85 C |
关键差异点
- Lower 9.2V/8.4V UVLO with 800 mV of hysteresis （对比 UC3825DW)
- Programmable 80% maximum duty cycle clamp （对比 UC3825DW)
- Higher 1 MHz switching capability vs lower-frequency competitors （对比 SG2525DW)
- 1.5 A peak source output drive （对比 SG2525DW)
- Available in AEC-Q100 automotive grade (UC2825Q1DWTR) （对比 SG3525DW)
设计说明
Place RT and CT components close to their respective IC pins to minimize parasitic capacitance that could distort oscillator waveforms. Use a ground-return trace from CT/RT ground pads back to the IC GND pin (pin 10) to avoid ground bounce coupling into the oscillator. Keep oscillator traces away from the OUTA/OUTB switching node traces (pins 11/12) to prevent frequency jitter.
The UC2825 max duty cycle is clamped at 80% via the SS/clamp pin. For forward converter topologies that require duty cycle >80%, choose UC3825 series with 100% duty cycle capability. Also note that current-limit resistor values must be selected assuming the 1.0V CS threshold; use Kelvin connections to the current-sense resistor to avoid ground-loop errors that shift the effective threshold.
Estimated: At VCC=30V, switching 1 MHz with 1A peak output current, power dissipation in the UC2825 output stage can reach 1W worst case. The 16-SOIC (DW) package has theta_JA of approximately 80-100 C/W (per package datasheet), so junction-to-ambient temperature rise could approach 100 C without copper pour. Use at least 1 square inch of copper pour on the SOIC thermal pad area for reliable operation.
Add 0.1 uF ceramic bypass close to VCC (pin 13) and a 1-10 uF bulk capacitor on the 5.1V REF pin (pin 14) to filter switching noise. The internal 5.1V reference supplies both error amplifier and oscillator sections; reference instability directly translates to PWM jitter. Use low-ESR ceramic capacitors with ESR <100 mohm for best reference stability.
Route the CS (current sense) trace as a Kelvin connection directly from the sense resistor to the ILIM pin (pin 9), avoiding any shared path with high-current switching returns. The shunt resistor should be a low-inductance type (e.g. four-terminal current shunt) at switching frequencies above 100 kHz. Ground the CS-return trace back to the shunt's ground terminal, not to the IC GND pin, to prevent switching-current noise injection into the current-limit comparator.
合规信息
RoHS and REACH compliant per the Texas Instruments product page. Not AEC-Q100 qualified in the standard UC2825DWTR; choose UC2825Q1DWTR for AEC-Q100 automotive applications.
