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UC3842AD8

UC3842AD8 – TI Current-Mode PWM Controller, 8-SOIC, Active

MPNUC3842AD8
Active

Texas Instruments UC3842AD8, current-mode PWM controller, 8-SOIC package, 10V–30V supply, 96% max duty cycle, up to 500 kHz switching frequency, commercial temperature range 0°C to 70°C.

$1.3300Ref. price · indicative, final on quote
Packaging8-SOIC (0.154", 3.90mm Width)
RoHSROHS3 Compliant
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

UC3842AD8 specifications
ParameterValue
Output typeTransistor Driver
MountingSurface Mount
Voltage - supply (Vcc (Vdd))10V ~ 30V
Frequency - switchingUp to 500kHz
I/O channels1
Output phases1
Duty cycle96%
Operating temperature0°C~70°C(TA)
PackageTube
FunctionStep-Up, Step-Down, Step-Up/Step-Down
TopologyBoost, Buck, Flyback, Forward
Clock syncNo
Case8-SOIC (0.154\", 3.90mm Width)
Control featuresFrequency Control
Output configurationPositive, Isolation Capable
Synchronous rectifierNo

Product details

Current-mode PWM controller for isolated and non-isolated topologies

Texas Instruments UC3842AD8 is a current-mode PWM controller supporting boost, buck, flyback, and forward converter topologies with a single transistor-driver output. The 10V to 30V supply range covers standard 12V and 24V bias rails found in industrial and telecom power supplies. The 96% maximum duty cycle allows high step-up ratios in boost and flyback designs without pulse-skipping at high line. Switching frequency reaches up to 500 kHz, enabling smaller transformer and inductor cores compared to lower-frequency controllers.

Supply rail and temperature constraints for BOM fit

For industrial or automotive environments, the LM5150QURUMRQ1 offers -40°C to 150°C operation and AEC-Q100 qualification, though it is a boost-only controller with 87% max duty cycle. Unlike the dual-output UCC2806DWTR which includes synchronous rectification and a 50% max duty cycle, the UC3842AD8 provides a single output with 96% duty — better suited for single-switch flyback and forward converters where high duty is needed.

Active production — no end-of-life risk on this BOM line

Frequently asked questions

Is UC3842AD8 compatible with UC3843AD8?

The UC3842AD8 and UC3843AD8 share the same pinout and package, but differ in the undervoltage lockout thresholds. The UC3842AD8 has a 16V/10V start/stop threshold; the UC3843AD8 uses 8.4V/7.6V. Verify the bias rail voltage before substituting.

Can UC3842AD8 be used in a flyback converter?

Yes. The UC3842AD8 supports flyback topology with a single transistor driver output and up to 96% duty cycle, making it suitable for single-switch flyback designs up to 500 kHz.