MILPITAS, CA – September 28, 2009 – Linear Technology Corporation announces the
LT3980, a 2A, 58VIN step-down switching regulator with Burst Mode® operation to
maintain quiescent current under 85uA. The LT3980 operates within a VIN range of 3.6V
to 58V, with overvoltage lockout protection against transients as high as 80V, making
the device ideal for load dump and cold-crank conditions commonly found in automotive
applications. Its internal 3.4A switch can deliver up to 2A of continuous output
current at voltages as low as 0.79V. The LT3980’s Burst Mode operation provides
ultralow quiescent current, well suited for applications such as automotive or telecom
systems, which have always-on circuits and demand optimal battery life. Switching
frequency is user programmable from 100kHz to 2.4MHz, enabling the designer to maximize
efficiency while avoiding critical noise-sensitive frequency bands. The combination of
a 3mm x 4mm DFN-16 package (or thermally enhanced MSOP-16E) and high switching
frequency keeps the LT3980’s external inductor and capacitors small, providing a
compact, thermally efficient footprint.
The LT3980 utilizes a high efficiency 3.4A, 200mOhm switch, with the necessary boost
diode, oscillator, control and logic circuitry integrated into a single chip. Its catch
diode current sense (DA pin) protects the circuit during input voltage transients even
at high switching frequencies. Low ripple Burst Mode® operation maintains high
efficiency at low output currents while keeping output ripple below 15mVPK-PK. Special
design techniques used in the LT3980
enable high efficiency over a wide input voltage range, and the device’s current mode
topology enables fast transient response and excellent loop stability. Other features
include external synchronization (from 250kHz to 2MHz), a power good flag and
soft-start capability.
Pricing for the LT3980EDE and LT3980EMSE starts at $3.55 each, for 1,000-piece
quantities. The LT3980IDE and LT3980IMSE are guaranteed to operate from a -40°C to
125°C operating junction temperature, priced at $4.18 each, in 1,000-piece quantities.
The LT3980HMSE is guaranteed to operate from a -40°C to 150°C operating junction
temperature and is priced at $4.43 in 1,000 piece quantities. All versions are
available from stock. For more information, visit www.linear.com.
Summary of Features: LT3980
- Wide Input Range: Operation from 3.6V to 58V
- Overvoltage Lockout
Protects Circuits Through 80V Transients
- 2A Maximum Output Current
- Low Ripple (<15mVP-P) Burst Mode® Operation:
- IQ = 85uA at 12VIN to 3.3VOUT
- Adjustable Switching Frequency: 100kHz to 2.4MHz
- Low Shutdown Current: IQ < 1uA
- Catch Diode Current Sense Protects Circuit Through Short-Circuit & Input
Overvoltage
- Synchronizable Between 250kHz to 2MHz
- Power Good Flag
- Saturating Switch Design: 200mOhm On-Resistance
- Thermal Protection
- Soft-Start Capability
- Small 16-Pin Thermally Enhanced MSOP & 3mm × 4mm DFN Packages