LTC3890-2
60V Low IQ, Dual, 2-Phase Synchronous Step-Down DC/DC Controller
Top
Overview
Features and Benefits
- Wide VIN Range: 4V to 60V (65V Abs Max)
- Low Operating IQ: 50µA (One Channel On)
- Wide Output Voltage Range: 0.8V ≤ VOUT ≤ 24V
- RSENSE or DCR Current Sensing
- Out-of-Phase Controllers Reduce Input Capacitance and Power Supply Induced Noise
- Phase-Lockable Frequency (75kHz to 850kHz)
- Programmable Fixed Frequency (50kHz to 900kHz)
- Selectable Continuous, Pulse-Skipping or Low Ripple Burst Mode® Operation at Light Loads
- Selectable Current Limit
- Very Low Dropout Operation: 99% Duty Cycle
- Adjustable Output Voltage Soft-Start or Tracking
- Power Good Output Voltage Monitors
- Low Shutdown IQ : < 14µA
- Internal LDO Powers Gate Drive from VIN or EXTVCC
- Small Low Profile (0.75mm) 5mm × 5mm QFN Package
- AEC-Q100 Qualified for Automotive Applications
Product Details
The LTC3890-2 is a high performance dual step-down switching regulator DC/DC controller that drives all N-channel synchronous power MOSFET stages. A constant frequency current mode architecture allows a phase-lockable frequency of up to 850kHz. Power loss and noise due to the ESR of the input capacitor are minimized by operating the two controller output stages out-of-phase.
The 50μA no-load quiescent current extends operating run time in battery-powered systems. OPTI-LOOP® compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. A wide 4V to 60V input supply range encompasses a wide range of intermediate bus voltages and battery chemistries.
Independent TRACK/SS pins for each controller ramp the output voltages during start-up. Current mode control limits the inductor current during short-circuit conditions. The PLLIN/MODE pin selects among Burst Mode operation, pulse-skipping mode, or continuous conduction mode at light loads. For versions with different and/or additional features, see the LTC3890 family summary, Table 1, in the Pin Functions section of this data sheet.
| LTC3890 | LTC3890-1 | LTC3890-2 | LTC3890-3 | |
| Adjustable Current Limit | Yes | No | Yes | No |
| CLKOUT/PHASMD for Multiphase Operation |
Yes | No | Yes | No |
| Number of PGood Outputs |
2 | 1 | 2 | 1 |
| OVP – Bottom Gate Crowbar |
Yes | Yes | No | No |
| Current Limit Foldback | Yes | Yes | No | No |
| Light Load Operation when Synced to External Clock |
Forced Continuous | Forced Continuous | Pulse Skipping | Pulse Skipping |
| SENSE Pins Common Mode Range |
Common Mode < 0.5V Requires VFB < 0.65V |
Common Mode < 0.5V Requires VFB < 0.65V |
Not Dependant on VFB. Easy to make a non-synchronous Boost or SEPIC |
Not Dependant on VFB. Easy to make a non-synchronous Boost or SEPIC |
| Package | 5X5 QFN-32 | SSOP-28 | 5X5 QFN-32 | SSOP-28 |
Applications
- Automotive Always-On Systems
- Battery Operated Digital Devices
- Distributed DC Power Systems
Product Lifecycle
Recommended for New Designs
This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.
Evaluation Kits (1)
Documentation & Resources
-
R526 Reliability Data3/26/2018
-
DC2236A-A - Demo Manual9/22/2014
Tools & Simulations
LTspice
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
To launch ready-to-run LTspice demonstration circuits for this part:
Step 1: Download and install LTspice on your computer.
Step 2: Click on the link in the section below to download a demonstration circuit.
Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.
Models for the following parts are available in LTspice:
LTC3890
LTC3890-1
LTC3890-2
LTC3890-3
LTpowerCAD
LTpowerCAD® is a power supply design program which selects power stage components, provides detailed power efficiency, shows quick loop Bode plot stability and load transient analysis, and can export to LTspice for simulation.
To open the project file for this circuit:
Step 1: Download and install LTpowerCAD on your computer.
Step 2: Click on the link(s) in the section below to download part-specific project files.
Step 3: If the project file doesn't run, right-click the link and select "Save Target As." Then start the LTpowerCAD tool and open the project file by selecing "Open Project" from the "File" menu.
LTpowerCAD Project Files
Design tools for the following parts are available in LTpowerCAD:
LTC3890
LTC3890-2
Product Recommendations
LTC3890-2 Companion Parts
Design Resources
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.View our quality and reliability program and certifications for more information.
PCN-PDN Information
Select a model from the dropdown below to subscribe to PCN/PDN notifications and view past notifications as well.
Support & Discussions
Sample & Buy
Ordering FAQs
See our Ordering FAQs for answers to questions about online orders, payment options and more.
Buy Now Pricing
(**) Displayed Buy Now Price and Price Range is based on small quantity orders.
List Pricing
(*)The 1Ku list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.
Lead Times
Please see the latest communication from our CCO regarding lead times.
Sampling
A Sample link will be shown above, next to the part, only for parts that are included in our sample program. Selecting the Sample button will redirect to the third-party ADI Sample Site. The part selected will carry over to your cart on this site once logged in. Please create a new account there if you have never used the site before. Contact SampleSupport@analog.com with any questions regarding this Sample Site.
Evaluation Boards
Pricing displayed is based on 1-piece.
Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.
Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.