ULN2068B STMicroelectronics Integrated Circuit (Dual-In-Line Packages) In Stock
STMicroelectronics ULN2068B is a quad high-current Darlington transistor array with logic-level compatible inputs, capable of sinking current for driving relays, solenoids, and lamps in a 16-pin DIP package. Available from stock with worldwide shipping.
- Manufacturer
- STMicroelectronics
- Package
- Dual-In-Line Packages
- Pin Count
- 16
- Lifecycle
- ACTIVE
- Datasheet
- ULN2068B Datasheet PDF
- Category
- Integrated Circuit
- Price
- From $2.5257(MOQ 25)
- Temp Range
- -20.0°C to 85.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
What are the key features of ULN2068B?
- Quad Darlington NPN transistor array with high-current sink output capability and built-in transient-suppression diodes for inductive load protection
- Logic-level compatible inputs for direct interfacing with TTL, CMOS, and microcontroller outputs without additional drive circuitry in a 16-pin DIP package
- 4-channel peripheral driver with current-sink output configuration ideal for relay coil, solenoid, stepper motor winding, and lamp driving applications
What is ULN2068B used for?
The ULN2068B is used in industrial control systems to drive relay coils, solenoids, and DC motors directly from logic-level signals such as microcontroller GPIO outputs or PLC outputs. Its 4 independent Darlington channels with built-in flyback diodes simplify inductive load driving without external protection components. The 16-pin DIP package makes it convenient for through-hole prototypes and panel controller boards in factory automation and HVAC control applications.
What are the specifications of ULN2068B?
| Factory Lead Time | 10Weeks |
| YTEOL | 5.62 |
| Additional Feature | LOGIC LEVEL COMPATIBLE |
| Built-in Protections | TRANSIENT |
| Driver Number of Bits | 4 |
| Interface IC Type | BUFFER OR INVERTER BASED PERIPHERAL DRIVER |
| JESD-30 Code | R-PDIP-T16 |
| JESD-609 Code | e3 |
| Number of Functions | 4 |
| Output Current Flow Direction | SINK |
| Output Current-Max | 1.5A |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | DIP16,.3 |
| Package Shape | RECTANGULAR |
| Package Style | IN-LINE |
| Peak Reflow Temperature (Cel) | NOT SPECIFIED |
| Qualification Status | Not Qualified |
| Supply Voltage-Nom | 5V |
| Surface Mount | NO |
| Technology | BIPOLAR |
| Temperature Grade | OTHER |
| Terminal Finish | Tin (Sn) |
| Terminal Form | THROUGH-HOLE |
| Terminal Pitch | 2.54mm |
| Terminal Position | DUAL |
| Time@Peak Reflow Temperature-Max (s) | NOT SPECIFIED |
| Turn-off Time | 1.5 µs |
| Turn-on Time | 1 µs |
| Package | Dual-In-Line Packages |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| ECCN | EAR99 |
| HTS Code | 8542.39.00.60 |
| Country of Origin | Mainland China, Malaysia |
Where can I find the ULN2068B datasheet?
ULN2068B Datasheet DownloadOfficial datasheet from STMicroelectronics
What are equivalent replacements for ULN2068B?
No known alternates. Submit an RFQ and our team can suggest alternatives.
Frequently Asked Questions
What output current can each channel of the ULN2068B sink when driving relay coils?
Each Darlington output channel of the ULN2068B can sink a continuous collector current of up to 1.5 A, with peak currents suitable for energizing relay coils drawing 500 mA to 1 A at supply voltages up to 50 V. The built-in transient suppression diodes clamp inductive kickback during relay de-energization, protecting the driver and logic supply.
Are the ULN2068B inputs compatible with 3.3 V microcontroller GPIO signals for direct interfacing?
The ULN2068B inputs are logic-level compatible and can be driven by TTL and CMOS signals. At 3.3 V input, the Darlington base voltage threshold allows reliable turn-on, and at 5 V the input current is typically below 1 mA, making it directly drivable from most 3.3 V or 5 V microcontroller GPIO pins without additional resistors or level shifters.
How does the ULN2068B built-in transient protection simplify inductive load driving compared to discrete transistor circuits?
Each output channel of the ULN2068B integrates a freewheeling diode between the collector and the COM pin, suppressing inductive transients from relay or solenoid coils without external components. In a discrete NPN Darlington circuit, a separate 1N4001 or Schottky diode plus base resistors are needed per channel, whereas the ULN2068B consolidates 4 protected drivers into a single 16-pin DIP package.
For driving a 4-phase stepper motor from a microcontroller, how does the ULN2068B configuration work?
The ULN2068B provides 4 independent sink-current channels, one per stepper phase winding. Each channel handles winding currents up to 1.5 A and supply voltages up to 50 V, covering most small NEMA 17 stepper motors rated at 12 V to 24 V. The microcontroller sequences 4 GPIO outputs at step rates from full-step to microstepping frequencies, while the ULN2068B Darlington gain ensures reliable switching from 3.3 V or 5 V logic.
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Why Buy from FindMyChip
About STMicroelectronics
STMicroelectronics is a global semiconductor leader serving customers across the spectrum of electronics applications. ST's products are found in a wide range of applications including automotive, industrial, personal electronics, and communications.
| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 25+ | $2.9264 | $73.16 |
| 100+ | $2.7567 | $275.67 |
| 250+ | $2.6869 | $671.73 |
| 1000+ | $2.6100 | $2610.00 |
| 2000+ | $2.5740 | $5148.00 |
| 4000+ | $2.5257 | $10102.72 |
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