nPM1300 is a highly integrated Power Management IC (PMIC) for rechargeable applications. It is design compatible with an nRF52, nRF53, or nRF54 Series System on Chip (SoC), nRF91 Series System in Package (SiP), and third party host devices for developing low-power wireless solutions.
nPM1300 has several power and system management features that can be implemented with dedicated components. Power management is achieved through flexible power regulation and a linear-mode lithium-ion (Li-ion), lithium-polymer (Li-poly), and lithium iron phosphate (LiFePO4) battery charger in a compact 3.1x2.4 mm WLCSP or 5x5 mm QFN32 package. A minimum of five passive components are required.
nPM1300 supports charging up to 800 mA and delivers up to 500 mA of adjustable regulated voltage. Power is supplied to external components from two configurable, dual mode 200 mA BUCK regulators, and two dual purpose 50 mA LDO/100 mA load switches. In addition, an unregulated power rail, VSYS, delivers up to 1 A when powered from battery, or up to 1.5 A when powered from a USB port configured as DCP. The maximum total current on VSYS is 1.5 A.
The host can read battery temperature, voltage, and current, which are utilized by a fuel gauge algorithm in the nRF Connect Software Development Kit. The fuel gauge provides the application with a battery state-of-charge estimate comparable to Coulomb counters at a significantly lower power consumption.
Low quiescent current (IQ) extends battery life during shipping and storage with Ship mode. Battery life can also be extended during operation with auto-controlled Hysteretic mode for high efficiency down to 1 µA load currents.
The integrated system management features reduce the cost and size of applications. The following integrated features are found in the device:
- System-level watchdog
- Intelligent power-loss warning
- Ship and Hibernate modes for increased battery life
- Up to 5 GPIO pins and 3 LED drivers
- System Monitor
- Ultra-low power, high accuracy fuel gauge tailored for embedded IoT applications
System management features and I/Os are configured through an I2C compatible two-wire Interface (TWI).
The nPM1300 Evaluation Kit provides simple evaluation and code-free configuration of nPM1300. Connecting to the nPM PowerUP app found in nRF Connect for Desktop enables the nPM1300 settings to be easily configured through an intuitive GUI and exported as code to be implemented in your MCU's application.
Block diagram
The block diagram illustrates the overall system.
In-circuit configurations
The device is configurable for different applications and battery characteristics through input pins.
The following pins must be configured before power-on reset. For the full pin list, see Pin assignments.
| Pin | Function | Reference |
|---|---|---|
| VDDIO | Supply for the TWI control interface and GPIOs | Interface supply, GPIO — General purpose input/output |
| VSET1 | BUCK1 enable and VOUT1 voltage level selection at power-on reset | BUCK — Buck regulators |
| VSET2 | BUCK2 enable and VOUT2 voltage level selection at power-on reset | BUCK — Buck regulators |
| CC1, CC2 | USB charger detection (USB Type-C) | USB port detection |
System description
The device has the following core components that are described in detail in their respective chapters.
The system regulator (SYSREG) is supplied by VBUS. It supports 4.0 V to 5.5 V for internal functions and tolerates transient voltages up to 22 V. Overvoltage protection is implemented for both internal and external circuitry. SYSREG also implements current limiting for VBUS to comply with the USB Type-C specification. SYSREG supports Type-C charger detection.
The battery charger (CHARGER) is a JEITA compliant linear battery charger for lithium-ion (Li-ion), lithium-polymer (Li-poly), and lithium iron phosphate (LiFePO4) batteries. CHARGER controls the charge cycle using a standard Li-ion charge profile. CHARGER implements dynamic power-path management regulating current in and out of the battery, depending on system requirements, to ensure immediate system operation from VBUS if the battery is depleted. Safety features, such as battery temperature monitoring and charger thermal regulation are supported.
Two independent, highly efficient buck regulators (BUCK) supply the application circuitry and offer several output voltage options. BUCK is controlled through registers or GPIO pins. Default output voltage can be set with external resistors.
The two load switches (LOADSW/LDO) can function as switches or linear voltage regulators to complement the power distribution network. LOADSW/LDO is controlled through registers or GPIO pins.
The System Monitor provides measurements for battery voltage, battery current, VBUS, battery, and die temperature.
- General purpose input
- Control input
- Output
- BUCK[n] control
- LOADSW[n] control
The device also features Ship and Hibernate modes, the lowest quiescent current states. They disconnect the battery from the system and reduce the quiescent current of the device to extend battery life. Hibernate mode can be utilized during normal operation as the device can autonomously wake-up after a preconfigured timeout. This makes it possible to extend battery life to the maximum capacity.
Power-on reset (POR) and brownout reset (BOR)
Supported battery types
The charger supports rechargeable Li-ion, Li-polymer, or LiFePO4 batteries.
- Overvoltage protection
- Undervoltage protection
- Overcurrent discharge protection
- Thermal fuse to protect from overtemperature (if NTC thermistor is not present)
Thermal protection
A global thermal shutdown is triggered when the die temperature exceeds the operating temperature range, see TSD. All device functions are disabled in thermal shutdown. The device functions are re-enabled when the temperature is sufficiently reduced according to a hysteresis TSDHYST. The die temperature limit is only monitored when charging is enabled or when a BUCK is enabled and is in PWM mode.
A secondary mechanism disables the charger when the die reaches the host software programmable temperature of DIETEMPSTOP . Once this temperature is reached, charging stops but all other functionality remains active. Charging restarts when the die temperature reaches the host software programmable temperature of DIETEMPRESUME.
System efficiency
Shown here is the characterization of the power path system efficiency under different load current conditions.
In the following figure, the load current is swept from 100 nA to 200 mA and back to capture mode change hysteresis.
Electrical characteristics
The following graphs show quiescent current characteristics.
System electrical specification
| Symbol | Description | Min. | Typ. | Max. | Unit |
|---|---|---|---|---|---|
| IQSHIP | Ship mode quiescent current | 370 | nA | ||
| IQSHIPT | Hibernate mode quiescent current | 500 | nA | ||
| IQBAT | Quiescent current, battery operation, all BUCKs and LDOs disabled, VBUS disconnected | 600 | nA | ||
| Quiescent current, battery operation, one BUCK enabled in Auto mode, no load, VBUS disconnected | 800 | nA | |||
| Quiescent current, battery operation, both BUCKs enabled in Auto mode, no load, VBUS disconnected | 1100 | nA | |||
| Quiescent current, battery operation, one BUCK enabled in PWM mode, VOUT=1.8 V, no load, VBUS disconnected | 4.0 | mA | |||
| Quiescent current, battery operation, both BUCKs enabled in PWM mode, VOUT=1.8 V, no load, VBUS disconnected | 7.1 | mA | |||
| TSD | Thermal shutdown threshold | 120 | °C | ||
| TSDHYST | Thermal shutdown hysteresis | 20 | °C | ||
| IOUTVSYS | Maximum VSYS DC load current when powered from battery (VBUS=0 V, VSYS>VSYSPOF) | 1.0 | A | ||
| Maximum VSYS DC load current when powered from VBUS, or from both VBUS and battery (VBUS=5 V, VSYS>VSYSPOF) | 1.5 | A |