27 Jun ULNA, ULNA. Eight Darlington arrays. Datasheet – production data. Features. • Eight Darlington transistors with common emitters. The ULNA datasheet specifies that it is a high-voltage, high-current Darlington transistor array. The device consists of eight npn Darlington pairs. ULN ULN SEMICONDUCTOR. TECHNICAL DATA. OCTAL PERIPHERAL. DRIVER ARRAYS. PIN CONNECTIONS. Order this document by .

Author: Mezitaur Arakree
Country: France
Language: English (Spanish)
Genre: Personal Growth
Published (Last): 11 August 2005
Pages: 412
PDF File Size: 20.93 Mb
ePub File Size: 17.54 Mb
ISBN: 419-5-58588-784-9
Downloads: 1310
Price: Free* [*Free Regsitration Required]
Uploader: Vigar

I have a 5V power supply that I drop to 3.

I didn’t check the specs on the uln2803a datasheet, but a 60V 27amp TO package cost less than a TO92, 1amp package. Saturday, January 10, Sign up using Facebook.

STMicroelectronics ULNA – ULNA – PDF Datasheet – High CurrentDrivers In Stock |

This prevents high voltages being generated datazheet protects the transistor. You are correct but see my update with concerns uln2803a datasheet the voltage available for the coils. Sign In or Register to comment. By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policy uln2803a datasheet, and our Terms of Service. The resultant current gain is the product of those of the two component transistors:.

Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

Texas Instruments

Hey I want to use the ULN to interface to high current devices. Without the free-wheel diode the voltage may still go high enough to damage the transistor switch.


Note the rather high collector-emitter saturation voltage. Base current is determined by voltage input divided by base resistance which is approx 10k ohms. Wed Aug 15, Uln2803a datasheet Darlington transistor also known uln2803a datasheet Darlington pair achieves very high current amplification by connecting two bipolar transistors in direct DC coupling so the current amplified by the first transistor is amplified further by the second one. That means that over the diode 3.

Forum Update – Announcement about May 10th, update and your password. Yln2803a further, stacking one chip on top of another, both dahasheet uln2803a datasheet physically, has been done. Sat Aug 18, 6: So that’s the total current for all outputs combined uln2803a datasheet it all flows out of the common GND pin. At mA you can only drive 5 outputs.

The only constraint is that they share a common positive. Views Read Edit View history. Who is online Users browsing this forum: So having 3V3 attached to uln2803a datasheet COM port will not be an issue? No registered users and 10 guests. Thank you for the clarification!

For a given relay size the power required will be the same for the various coil supply voltage options. Interestingly uln2803a datasheet, you can get TO92 package mosfet’s that will carry an amp, but TO package mosfets will cost less and carry more amps.

v – ULN – do i need COM(VSUP) for relays ? – Electrical Engineering Stack Exchange

Also see figure 8, where you can see that the test is done with an input voltage of just 3. It features common-cathode flyback diodes for switching inductive loads. The ULN is known uln2803a datasheet its high-current, high-voltage capacity.


Wikimedia Commons uln2803a datasheet media related to ULN Typical usage of the ULNA is in driver circuits for relayslamp and LED displaysstepper motors, logic buffers and line drivers. In other projects Wikimedia Commons. Because the output transistor is driven by another one in the Darlington arrangement the output transistor doesn’t saturate as well as with a single stage output.

That means the transistor will be driven uln2803a datasheet open! When switching an inductive load with a uln2803a datasheet it is necessary to use a uln2803a datasheet diode to conduct the inductive “kick” of the inductor as the current falls to zero.

In other words, when uln2803a datasheet is switched on the voltage drop between the connection to the load device and ground is substantial — not 0.

Also the package total heat dissapation is 2.

Can anyone help me out and tell me how much it will be. A better solution would be to power the relays from a higher voltage supply uln2803a datasheet either the 5 V, if available, or whatever unregulated supply is powering your uln2803a datasheet.