Texas Instruments ULN2003LV Relay Driver Supports 1.8 V to 5 V

Texas Instruments ULN2003LV relay driver

Texas Instruments rolled out the ULN2003LV relay driver. The ULN2003LV is a low-voltage and low power upgrade of TI’s ULN2003 family of 7-channel Darlington transistor array. It is the first fully-integrated, seven-channel relay driver that can support low-voltage relays from as low as 1.8 V up to 5 V. The device is available in 10mm x 4mm, 16-pin SOIC and 5.1mm x 4.5mm, 16-pin TSSOP packages. The TI ULN2003LV relay driver is priced at 15¢ each in 100-unit quantities.

TI ULN2003LV relay driver functional diagram

The TI ULN2003LV integrated circuit (IC) replaces a handful of discrete components with a single device to drive lower voltages for data relays and rails within telecommunications equipment. The ULN2003LV relay driver can reduce board space by up to 80%, while lowering power consumption and cost.

The ULN2003LV sink driver features 7 low output impedance drivers for low voltage relay and inductive coil applications. The low impedance drivers minimize on-chip power dissipation (up to 5 times lower for typical 3V relays).

The TI device supports 3.3V to 5V CMOS logic input interface. It includes an improved input interface that minimizes the input DC current drawn from the external drivers. The ULN2003LV also features an input RC snubber that improves performance in noisy operating conditions. The ULN2003LV channel inputs feature an internal input pull-down resistor thus allowing input logic to be tri-stated.

Each output of the ULN2003LV includes an internal free-wheeling diode connected in a common-cathode configuration at the COM pin.

The relay driver increases current sink capability by combining several adjacent channels in parallel. Under typical conditions, the ULN2003LV can support up to 1.0A of load current when all 7-channels are connected in parallel.

Texas Instruments ULN2003LV Relay Driver Features

  • 7-channel high current sink drivers
  • Supports up to 8V output pull-up voltage
  • Supports a wide range of 3V-to-5V relay and inductive coils
  • Low output VOL of 0.4V (typical)
  • 100mA (typical) current sink per channel at 3.3V logic input
  • 140mA (typical) current sink per channel at 5.0V logic input
  • Compatible to 3.3V and 5.0V microcontrollers and logic interface
  • Internal free-wheeling diodes for inductive kick-back protection
  • Input RC snubber to eliminate spurious operation in noisy environment
  • Low input and output leakage currents
  • Easy to use parallel interface
  • ESD protection exceeds JESD 22 (2kV HBM, 500V CDM)
  • Available in 16-pin SOIC and TSSOP packages

More info: Texas Instruments ULN2003LV Relay Driver (pdf)