The XR77128 is a quad channel Digital Pulse Width Modulated (DPWM) step-down (buck) controller. A wide 4.75V to 25V input voltage range allows for single supply operation from standard power rails.
With integrated FET gate drivers, two LDOs for standby power and a 105kHz to 1.23MHz independent channel-to-channel programmable constant operating frequency, the XR77128 reduces overall component count and solution footprint and optimizes conversion efficiencies. A selectable digital Pulse Frequency Mode (DPFM) capable of better than 80% efficiency at light current load and low operating current allow for portable and Energy Star compliant applications. Each XR77128 output channel is individually programmable as low as 0.6V with a resolution as fine as 2.5mV and configurable for precise soft-start and soft-stop sequencing, including delay and ramp control.
The XR77128 operation is fully controlled via a SMBus-compliant I2C interface allowing for advanced local and/or remote reconfiguration, full performance monitoring and reporting as well as fault handling.
Built-in independent output overvoltage, over temperature, overcurrent and undervoltage lockout protections insure safe operation under abnormal operating conditions.
The XR77128 is offered in a RoHS compliant, "green"/halogen free 44-pin TQFN package.
- Quad channel step-down controller
- Digital PWM 105kHz to1.23MHz operation
- Individual channel frequency selection
- Patented digital PFM with ultrasonic mode
- Patented oversampling feedback
- Pin compatible to XRP7724 with added features
- Selectable DrMOS drive capability
- Additional GPIO configurability
- Current limit fault options
- Additional conditional fault options
- Improved output voltage accuracy
- 4.75V to 25V input voltage
- 4.75V to 5.5V and 5.5V to 25V input ranges
- 0.6V to 5.5V output voltage
- SMBus compliant - I2C interface
- Full monitoring and reporting
- 3 x 15V capable PSIO + 2 x GPIOs
- Full start/stop sequencing support
- Built-in thermal, overcurrent, UVLO and output overvoltage protections
- Onboard 5V and 3.3V standby LDOs
- Onboard non-volatile memory
- Evaluation Board, Demo Kit and Configuration Module (XCM) are available for evaluation and development purposes only
- Supported by PowerArchitect™ Design and Configuration Software
- Third-Party Programming Support
- Automotive infotainment
- Industrial control systems
- Audio systems
- Automatic test equipment
- Video surveillance systems
Parts & Purchasing
|Part Number||Pkg Code||Min Temp||Max Temp||Status||Buy Now||Order Samples|
Active - the part is released for sale, standard product.
EOL (End of Life) - the part is no longer being manufactured, there may or may not be inventory still in stock.
CF (Contact Factory) - the part is still active but customers should check with the factory for availability. Longer lead-times may apply.
PRE (Pre-introduction) - the part has not been introduced or the part number is an early version available for sample only.
OBS (Obsolete) - the part is no longer being manufactured and may not be ordered.
NRND (Not Recommended for New Designs) - the part is not recommended for new designs.
Quality & Environmental Data
|Part Number||RoHS | Exempt||RoHS||Halogen Free||REACH||MSL Rating / Peak Reflow||Package|
|XR77128ELB-F||N||Y||Y||Y||L3 / 260ᵒC||TQFN44 7x7|
Click on the links above to download the Certificate of Non-Use of Hazardous Substances.
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For material content, environmental, quality and reliability questions review the Quality tab or visit our Quality page.
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Frequently Asked Questions
Find the product page of the part that you want to get an evaluation board for and click on Parts & Purchasing. Example:
Find the icons under Buy Now or Order Samples:
Click on the Buy Now icon and see who has stock and click on the Buy button:
Alternatively, you can click on the Order Samples
If the icons are missing, then contact Customer Support.
In this example, we looked for XRA1201. Click on part number header or on the link at the bottom of the result. This brings you to the product page. For example:
Click on Parts & Purchasing, highlighted with the blue arrow above. The screen changes to:
Notice the status column and the “Show obsolete parts” link. A legend tells you the definition of the different statuses. Click on the “Show obsolete parts” link to see EOL or OBS part numbers along with the Active part numbers, the legend still present:
Another method to find out if a part is OBS or EOL is to click on SUPPORT at the top:
And then Product Change Notifications:
Type the part into the search, and click on one of the part numbers from the drop down menu. Then you can look for the Product Discontinuation Notice, which generally is at the top of the list, for example:
If you see this, it tells you that this particular orderable part has been discontinued and when the last order date is, or was. If you click on the file, then you can view the notice we sent about this if you purchased the part in the recent past. It may also advise of a replacement part. When an orderable part first becomes discontinued, Product Discontinuation Notices are sent are sent to those who have purchased the parts in the recent past, if purchased directly, with a dated opportunity to place a last order.
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