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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Frequently Asked Questions
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