The Original MAX77843 / MAX77833 Power Management IC (PMIC) is an OEM-grade integrated power controller engineered specifically for Samsung Galaxy logic board architectures, most notably the Galaxy S6 (SM-G920 series) and Galaxy S6 Edge (SM-G925 series), as well as select Galaxy Note 4 variants. Designated as U7000 on standard Samsung schematic layouts, this multi-function BGA chip integrates system-level power distribution, battery charging regulation, USB interface logic, and auxiliary buck-boost converters into a single silicon footprint.
When Samsung devices suffer electrical spikes, non-compliant third-party fast-charger overvoltages, or moisture ingress, the MAX77843 is frequently the primary point of failure. Replacing a burnt or internally shorted chip with this factory-tested replacement restores dead devices to full operating condition, resolves continuous battery drain, and clears charging hang-ups.
Failure Symptoms Fixed by MAX77843 Replacement
- Dead Boot / No Power: Phone fails to power on completely and registers zero amperage draw or drops immediately to 0mA when the power key is released.
- Secondary VDD Rail Short Circuits: Short to ground or abnormal diode mode readings on the peripheral filter capacitors and inductors surrounding the U7000 IC.
- Continuous Standby Leakage: Board draws static current (80mA–450mA+) on a DC bench power supply before prompt boot-up, leading to severe battery drain.
- Charging Circuit Failures: Device indicates charging on the screen but does not increase battery percentage (fake charging), or fails to recognize USB cables altogether.
- Thermal Hotspots: Rapid thermal rise detected directly on the MAX77843 package using a thermal camera or rosin spray during power-on attempts.
Technical Specification Matrix
Parameter Profile | Specification Details |
Component Part Number | MAX77843 (Cross-compatible/variant: MAX77833) |
Circuit Function | Primary / Sub Power Management IC (PMIC / Charging / OTG Logic) |
Schematic Designation | U7000 (Samsung Galaxy S6 / S6 Edge schematics) |
Package Style | Fine-Pitch Wafer-Level BGA |
Silicon Quality | 100% Original Brand New / Factory Tested |
Contact Metallurgy | High-precision pre-leveled solder ball matrix |
Primary Device Compatibility | Samsung Galaxy S6 (SM-G920F, G920I, G920A, G9200), Samsung Galaxy S6 Edge (SM-G925F, G925I, G925A, G9250), Galaxy Note 4 (Select variants: N9100 / N910F) |
Required Tools | Hot air rework station, micro-soldering iron, fine tweezers, quality BGA flux (e.g., Relife RL-428-OR) |
Professional Installation Guidelines
- Schematic & Diagnostic Verification: Using Borneo Schematics or boardview tools, verify that the short circuit originates from U7000 lines (such as VBUS, VBAT, or buck output rails) rather than secondary filtering capacitors.
- Component Removal: Shield nearby heat-sensitive components (such as baseband ICs and processor shielding frames) with thermal tape or copper foil. Apply high-activity BGA flux and heat the chip using a hot air station at 330°C–350°C with low airflow until the solder reflows cleanly, then lift the IC with precision curved tweezers.
- Pad Leveling & Cleaning: Wick off oxidized remaining solder from the motherboard pads using Chemtronics or Goot Wick with a broad bevel soldering iron tip. Clean thoroughly with 99% IPA until all pads are flat, bright, and uniform.
- Alignment & Soldering: Align the new MAX77843 with the pin-1 index dot on the PCB silkscreen. Apply a micro-layer of tacky flux and heat perpendicularly in slow circular motions until the chip self-aligns via surface tension.
- Post-Repair Inspection: Let the logic board cool naturally for 2–3 minutes. Re-check the surrounding coils and capacitors in diode mode to confirm the short circuit is completely cleared before powering on.
Package Contents:
- 5 × Original MAX77843 / MAX77833 Power IC (PMIC Chip)
