Integration Manual
Table Of Contents
- Document information
- Contents
- 1 System description
- 1.1 Overview
- 1.2 Architecture
- 1.3 Pin-out
- 1.4 Operating modes
- 1.5 Supply interfaces
- 1.5.1 Module supply input (VCC)
- 1.5.1.1 VCC supply requirements
- 1.5.1.2 VCC current consumption in LTE connected mode
- 1.5.1.3 VCC consumption in deep-sleep mode (low power mode and PSM enabled)
- 1.5.1.4 VCC current consumption in low power idle mode (low power mode enabled)
- 1.5.1.5 VCC current consumption in active mode (low power mode and PSM disabled)
- 1.5.2 Generic digital interfaces supply output (V_INT)
- 1.5.1 Module supply input (VCC)
- 1.6 System function interfaces
- 1.7 Antenna interfaces
- 1.8 SIM interface
- 1.9 Data communication interfaces
- 1.10 Audio
- 1.11 General purpose input / output (GPIO)
- 1.12 Reserved pin (RSVD)
- 2 Design-in
- 2.1 Overview
- 2.2 Supply interfaces
- 2.2.1 Module supply (VCC)
- 2.2.1.1 General guidelines for VCC supply circuit selection and design
- 2.2.1.2 Guidelines for VCC supply circuit design using a switching regulator
- 2.2.1.3 Guidelines for VCC supply circuit design using low drop-out linear regulator
- 2.2.1.4 Guidelines for VCC supply circuit design using a rechargeable battery
- 2.2.1.5 Guidelines for VCC supply circuit design using a primary battery
- 2.2.1.6 Guidelines for external battery charging circuit
- 2.2.1.7 Guidelines for external charging and power path management circuit
- 2.2.1.8 Guidelines for removing VCC supply
- 2.2.1.9 Additional guidelines for VCC supply circuit design
- 2.2.1.10 Guidelines for VCC supply layout design
- 2.2.1.11 Guidelines for grounding layout design
- 2.2.2 Generic digital interfaces supply output (V_INT)
- 2.2.1 Module supply (VCC)
- 2.3 System functions interfaces
- 2.4 Antenna interfaces
- 2.5 SIM interface
- 2.6 Data communication interfaces
- 2.6.1 UART interfaces
- 2.6.1.1 Guidelines for UART circuit design
- Providing 1 UART with the full RS-232 functionality (using the complete V.24 link)
- Providing 1 UART with the TXD, RXD, RTS, CTS, DTR and RI lines only
- Providing 1 UART with the TXD, RXD, RTS and CTS lines only
- Providing 2 UARTs with the TXD, RXD, RTS and CTS lines only
- Providing 1 UART with the TXD and RXD lines only
- Providing 2 UARTs with the TXD and RXD lines only
- Additional considerations
- 2.6.1.2 Guidelines for UART layout design
- 2.6.1.1 Guidelines for UART circuit design
- 2.6.2 USB interface
- 2.6.3 SPI interfaces
- 2.6.4 SDIO interface
- 2.6.5 DDC (I2C) interface
- 2.6.1 UART interfaces
- 2.7 Audio
- 2.8 General purpose input / output (GPIO)
- 2.9 Reserved pin (RSVD)
- 2.10 Module placement
- 2.11 Module footprint and paste mask
- 2.12 Schematic for SARA-R5 series module integration
- 2.13 Design-in checklist
- 3 Handling and soldering
- 4 Approvals
- 5 Product testing
- Appendix
- A Migration between SARA modules
- B Glossary
- Related documents
- Revision history
- Contact
SARA-R5 series - System integration manual
UBX-19041356 - R03 Design-in Page 44 of 123
Confidential
Figure 24 and the parts listed in Table 12 provide an application circuit example where the MPS
MP2617H switching charger / regulator with integrated power path management function provides
the supply to the cellular module. At the same time it also concurrently and autonomously charges a
suitable Li-Ion (or Li-Pol) battery with the correct pulse and DC discharge current capabilities and the
appropriate DC series resistance according to the rechargeable battery recommendations described
in section 2.2.1.4.
The MP2617H IC constantly monitors the battery voltage and selects whether to use the external main
primary supply / charging source or the battery as supply source for the module, and starts a charging
phase accordingly.
The MP2617H IC normally provides a supply voltage to the module regulated from the external main
primary source allowing immediate system operation even under missing or deeply discharged
battery: the integrated switching step-down regulator is capable to provide up to 3 A output current
with low output ripple and fixed 1.6 MHz switching frequency in PWM mode operation. The module
load is satisfied in priority, then the integrated switching charger will take the remaining current to
charge the battery.
Additionally, the power path control allows an internal connection from battery to the module with a
low series internal ON resistance (40 m typical), in order to supplement additional power to the
module when the current demand increases over the external main primary source or when this
external source is removed.
Battery charging is managed in three phases:
Pre-charge constant current (active when the battery is deeply discharged): the battery is
charged with a low current, set to 10% of the fast-charge current
Fast-charge constant current: the battery is charged with the maximum current, configured by
the value of an external resistor to a value suitable for the application
Constant voltage: when the battery voltage reaches the regulated output voltage (4.2 V), the
current is progressively reduced until the charge termination is done. The charging process ends
when the charging current reaches the 10% of the fast-charge current or when the charging timer
reaches the value configured by an external capacitor
Using a battery pack with an internal NTC resistor, the MP2617H can monitor the battery temperature
to protect the battery from operating under unsafe thermal conditions.
Several parameters as the charging current, the charging timings, the input current limit, the input
voltage limit, the system output voltage can be easily set according to the specific application
requirements, as the actual electrical characteristics of the battery and the external supply / charging
source: suitable resistors or capacitors must be accordingly connected to the related pins of the IC.