圖片僅供參考

UC3844AD8TR

Name: UC3844AD8TR
Rating: 4.7 (12 reviews)

IC REG CTRLR PWM CM 8SOIC

製造商
製造商。部分 #UC3844AD8TR
包 8-SOIC (0.154, 3.90mm Width)
資料表
有現貨的4832

+BOM RFQ

100%原創；新

24小時準備發貨

365天保修

RFQ&；獲得更多折扣

規格

Supplier	Texas Instruments
Package	Tape & Reel (TR),Cut Tape (CT)
ProductStatus	Active
OutputType	Transistor Driver
Function	Step-Up, Step-Down, Step-Up/Step-Down
OutputConfiguration	Positive, Isolation Capable
Topology	Boost, Buck, Flyback, Forward
NumberofOutputs	1
OutputPhases	1
Voltage-Supply(Vcc/Vdd)	10V ~ 30V
Frequency-Switching	Up to 500kHz
DutyCycle(Max)	48%
SynchronousRectifier	No
ClockSync	No
ControlFeatures	Frequency Control
OperatingTemperature	0°C ~ 70°C (TA)
MountingType	Surface Mount
Package/Case	8-SOIC (0.154, 3.90mm Width)

概述

Description

UC3844AD8TR is a current‑mode PWM controller from the UC3842/3844 family (TI/Unitrode). It is the control core for off‑line switch‑mode power supplies (flyback, buck/forward), driving an external power switch (MOSFET or transistor) from a feedback signal.
Key points:
- Type: 8‑pin PWM controller with current‑mode control
- Inputs/Protection: current sense input, feedback input from optocoupler, undervoltage lockout, overcurrent/short‑circuit protection, soft‑start
- Supply/drive: operates from about 4.5 to 40 V; frequency set by an external RT component
- External needs: requires a few passive components and an external power switch; feedback via optocoupler
- Packaging suffix: AD8TR denotes a specific variant package and tape‑and‑reel packaging; check the datasheet/distributor listing for exact details
Applications: primary‑side SMPS like wall adapters, phone/PC chargers, battery chargers, telecom supplies.
Note: consult the UC3844/AD8TR datasheet for exact electrical specs and pinout.

Features

UC3844AD8TR features (highlights):
- Fixed-frequency current-mode PWM controller for SMPS
- Switching frequency around 52 kHz (typical; fixed)
- Wide input range: 4.5–40 V for startup and operation
- Undervoltage lockout with hysteresis
- Leading-edge blanking on current-sense input
- Line feed-forward for improved line regulation
- Slope/valley current limit (cycle-by-cycle protection)
- Soft-start to limit inrush and improve reliability
- Internal 5 V reference for feedback network
- Error amplifier input for optocoupler feedback
- Single-ended output to drive a power MOSFET gate
- 8-pin package (D8TR) available in tape & reel
Applications: flyback, forward, and other isolated/non-isolated SMPS.

Package

8-pin package, typically SOIC-8 (surface-mount). The “TR” suffix indicates Tape & Reel packaging.

Pinout

- Pin count: 8 pins (8-pin packaging, e.g., SOIC/DIP).
- Function: UC3844AD8TR is an 8-pin current‑mode PWM controller for switching power supplies. It provides an oscillator, error amplifier, current-sense input, PWM comparator, slope compensation, undervoltage lockout, soft-start, overcurrent protection, and a gate-drive output to switch a power MOSFET. Used in flyback/forward/buck SMPS to regulate output voltage.

Manufacturer

Manufacturer: Texas Instruments (TI).
Kind of company: An American multinational semiconductor company that designs and manufactures analog, mixed-signal, and digital integrated circuits and processors for a wide range of applications.

Application

UC3844AD8TR is a current‑mode PWM controller for switch‑mode power supplies. Typical applications include:
- Flyback, buck, boost, and buck–boost converters
- Offline AC adapters and other SMPS for consumer electronics
- LED drivers
- Battery chargers
- Telecom, computer and industrial power supplies
- Compact, high‑efficiency DC‑DC converters with fast transient response

Equivalent

Common drop-in equivalents for UC3844AD8TR (current‑mode PWM controller) include:
- KA3842 and KA3844 (and KA3844A) from various vendors
- FAN3842 and FAN3844 (Fairchild)
Notes:
- These are functionally similar 8-pin current‑mode controllers; pinouts/specs can vary slightly.
- Always verify startup, reference, and pinout against your circuit and packaging. Other UC384x family parts (UC3842/3843) are related but may require tweaks.