PCA9422 - 640mA Charger+Gauge PMIC for i.MX RT500/600/700 | NXP
MPN: PCA9422 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.68 | $2.68 |
| 10 | $2.41 | $24.10 |
| 100 | $2.05 | $205.00 |
| 500 | $1.82 | $910.00 |
| 1,000 | $1.64 | $1,640.00 |
PCA9422 Overview
A PMIC (power management IC) is a highly integrated semiconductor that combines multiple power functions - battery charging, voltage regulation, load switching, and monitoring - into a single device. In the system hierarchy, a PMIC sits above individual regulators: instead of designing a discrete charger IC, multiple DC-DC converters, and fuel-gauge circuitry separately, the PCA9422 provides a complete power tree for a low-power microcontroller system on one chip, reducing bill-of-materials count, board area, and quiescent power consumption.
Key features include a linear battery charger with Constant Current (CC) and Constant Voltage (CV) charge phases capable of up to 640 mA, integrated battery gauging functionality, and targeting of NXP's ultra-low-power crossover MCU families - the i.MX RT500, i.MX RT600, and i.MX RT700. The high level of integration makes it suited to small-battery products where every square millimeter and every microamp of standby current matters.
Architecturally, the PCA9422 was designed in close conjunction with the i.MX RT500/RT600/RT700 power architecture, so its regulated rails and charge profile match the sequencing and brown-out requirements of those MCUs without external sequencing logic. The WLCSP packaging minimizes loop inductance and footprint, and on-chip charging control removes the need for a separate charger IC in wearables and hearables.
Typical applications include battery-powered wearables, hearables and smart-sensor nodes built around the i.MX RT500/RT600/RT700, and other small-battery microcontroller systems that need charging plus power distribution in one device.
When designing with this device, verify the charge current setting against your battery cell's 1C rating and confirm thermal dissipation of the linear charger at maximum VIN-to-VBAT differential - linear charging at 640 mA can dissipate significant power if the input rail is much higher than the battery voltage.
This page synthesizes distributor pricing, drop-in variant alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PCA9422 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PCA9422LUKZ
✅ Drop-In✓ In Stock
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View Datasheet →PCA9422BUKZ
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View Datasheet →PCA9422AUK
✅ Drop-In📋 Reference alternative (not in catalog)
PCA9422 Specifications
| Product Type | Charger and Gauge PMIC |
| Maximum Charge Current | 640 mA (linear charger) |
| Charge Method | Linear, Constant Current (CC) / Constant Voltage (CV) |
| Target Processors | i.MX RT500, i.MX RT600, i.MX RT700 |
| Package | 49-WLCSP (3 x 2.9 mm) |
| Mounting Type | Surface Mount (wafer-level chip-scale) |
| Integration | Charger + gauge + power management in single IC |
| Battery Gauging | Integrated |
| Application Domain | Low-power microcontroller and small-battery applications |
PCA9422 49-wlcsp (3 x 2.9 mm) Pin Configuration Guide
Pin configuration for PCA9422 (49-wlcsp (3 x 2.9 mm) package). Pin numbering, functions, and connection diagrams are defined in the manufacturer datasheet. Refer to it for the exact footprint and soldering guidelines.
No detailed pinout data available for PCA9422.
Refer to the datasheet for full pin configuration.
Typical Applications
PCA9422 is suitable for 6 applications: i.MX RT500 Wearables Power Supply, Hearables and True Wireless Audio, Battery-Powered IoT Sensor Nodes, Smart Medical Patch and Health Monitors, Portable Handheld Instruments, Smart Tags and Asset Trackers.
i.MX RT500 Wearables Power Supply
The PCA9422 fits wearable designs built on the i.MX RT500 because its power architecture was co-developed with that MCU family: the charger's 640 mA CC/CV profile, integrated gauging, and rail configuration align with RT500 sequencing requirements without external supervision logic. In a fitness band or smart ring, the PMIC sits between the USB input and the single-cell Li-ion battery, charging at up to 640 mA while its regulated outputs feed the RT500 core and peripherals. The 3 x 2.9 mm WLCSP conserves the tight board area typical of wearables. The trade-off of linear charging is heat at high VIN-VBAT differentials, so limit charge current or thermal budget accordingly.
Recommended
Hearables and True Wireless Audio
Hearable designs pair an i.MX RT600 or RT700-class processor with a very small battery, making the PCA9422's combination of 640 mA charger, integrated gauge, and chip-scale 49-ball package (3 x 2.9 mm) a strong fit. The charger's CC/CV profile safely charges the small cell from a case or USB input, while integrated gauging reports state of charge to firmware so the earbud can manage playback time predictions without a separate fuel-gauge IC. Because the gauge is on-chip, one less I2C device and one less footprint compete for space on the tiny PCB. Linear-charge dissipation is modest at hearable cell sizes but should still be budgeted during fast-charge from a 5 V case.
Recommended
Battery-Powered IoT Sensor Nodes
Low-power IoT sensor nodes using small rechargeable cells benefit from the PCA9422's single-IC integration: charger, gauge, and power management replace three discrete functions, cutting BOM count and quiescent overhead. The ultra-low-power design goal of the part matches battery-node duty cycles where the system sleeps most of the time and wakes to sample and transmit. Charging at up to 640 mA allows fast recovery from solar or USB trickle inputs, while the gauge lets firmware throttle transmission rates as the battery depletes. Verify the charger's termination and recharge thresholds against your cell specification, and use the i.MX RT600/RT700 SDK power examples to coordinate rail control with sleep modes.
Recommended
Smart Medical Patch and Health Monitors
Disposable and rechargeable medical patches built on i.MX RT500/RT600 MCUs require compact, safe, and monitorable power - exactly the PCA9422's value proposition. The integrated charger enforces a proper CC/CV lithium charge profile, protecting the small cell in a body-worn product, while on-chip gauging gives firmware the state-of-charge data needed for patient-facing battery indication and safe-shutdown decisions. The 49-WLCSP 3 x 2.9 mm footprint fits the curved, miniaturized PCBs typical of patches. For medical use, validate the charge safety behavior (thermal limits, fault response) from the NXP datasheet against your risk-management file, and budget linear-charger heat for skin-adjacent enclosures.
Recommended
Portable Handheld Instruments
Handheld meters and portable instruments based on i.MX RT-series crossover MCUs can use the PCA9422 to collapse their power tree into one chip: a 640 mA linear CC/CV charger accepts USB input, the integrated gauge drives an accurate battery indicator, and the PMIC rails supply the MCU and analog front end. Compared to a discrete charger-plus-LDO-plus-gauge design, the single 3 x 2.9 mm WLCSP reduces assembly steps and board area on space-constrained instrument PCBs. The main design consideration is thermal: sustained charging at 640 mA from a 5 V input into a partially discharged cell can dissipate on the order of a watt, so provide copper pour and verify the datasheet thermal data.
Recommended
Smart Tags and Asset Trackers
Rechargeable smart tags and asset trackers built around i.MX RT500/RT700 MCUs pair naturally with the PCA9422. The gauge is essential here: trackers live unattended for weeks, so firmware needs trustworthy state-of-charge data to schedule check-ins and low-battery alerts. The 640 mA charger permits fast top-ups from wireless-charging or USB-case inputs, and the ultra-low-power design minimizes drain between transmissions. The WLCSP package suits the thin, small form factors of tags. Design attention should go to the charger's input-source behavior - confirm input current limiting and weak-source handling in the NXP datasheet so the tag charges safely from small harvesters or charging cases.
Recommended
Recommended Products Summary
Engineering reference data for PCA9422 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PCA9422LUKZ | PCA9422BUKZ | PCA9422AUK |
|---|---|---|---|---|
| Package | 49-WLCSP (3 x 2.9 mm) | 49-WLCSP (3 x 2.9 mm) - same | 49-WLCSP (3 x 2.9 mm) - same | 49-WLCSP (3 x 2.9 mm) - same |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Max Charge Current | 640 mA (linear CC/CV) | 640 mA | 640 mA | 640 mA |
| Battery Gauging | Integrated | Integrated | Integrated | Integrated |
| Target Processors | i.MX RT500 / RT600 / RT700 | i.MX RT500 / RT600 / RT700 | i.MX RT500 / RT600 / RT700 | i.MX RT500 / RT600 / RT700 |
| Datasheet | NXP PCA9422 datasheet (26 pages per Alldatasheet listing) | Same PCA9422 datasheet | Same PCA9422 datasheet | Same PCA9422 datasheet |
Key Differentiators
- Co-designed power architecture for i.MX RT500/RT600/RT700 (vs Generic discrete charger + LDO + gauge solution)
- Integrated battery gauging (vs Standalone linear charger ICs without gauge)
- Chip-scale footprint advantage (vs QFN-packaged competing PMICs)
Design Notes
Estimated: the PCA9422 uses a linear charger, so charge-phase dissipation is approximately (VIN - VBAT) x ICHG. At a 5 V USB input charging a 3.0 V depleted cell at 640 mA, that is roughly 1.28 W into a 3 x 2.9 mm WLCSP - a high density for small boards. Mitigate by lowering programmed charge current when input voltage is high, spreading heat with copper pour connected to the thermal balls of the 49-ball array, and checking the NXP datasheet for any integrated thermal regulation feature that reduces current as the die heats. Never assume worst-case charge current is sustainable in a sealed wearable enclosure.
WLCSP assembly requires exact land-pattern matching to the datasheet ball map for the 49-ball 3 x 2.9 mm package, including the ball A1 corner indicator orientation on your PCB silkscreen. Because chip-scale packages have no leads to absorb stress, place the PMIC away from board flex zones and connector edges, and follow the NXP datasheet footprint recommendation for pad geometry (typically non-solder-mask-defined). Route high-current charge paths (VIN, battery, ground) with adequate copper width for 640 mA continuous, and keep the gauge sense connections Kelvin-routed to the battery terminal for accuracy.
Three frequent mistakes with this class of charger-gauge PMIC. First, do not set charge current above your cell's rated fast-charge capability - the 640 mA maximum is a device limit, not a battery requirement. Second, always verify the ordering code: PCA9422LUKZ, PCA9422BUKZ and PCA9422AUK are ordering variants of the same silicon, but confirm the exact suffix you qualify with your CM so second-sourcing on BOMs does not fail at the suffix level. Third, initialize the gauge and charger configuration registers per the NXP i.MX RT-series BSP example code - relying on power-up defaults can produce incorrect state-of-charge reporting.
Compliance Information
The -Z suffix on PCA9422LUKZ and PCA9422BUKZ conventionally denotes NXP RoHS-compliant/lead-free versions, but explicit RoHS/REACH certificates were not present in the Verified Web Data; confirm via NXP product page before regulatory documentation.
