ARDUINO INTERFACE EXPANSION BOARD

It is an interface board for sensors. It has the same footprint as «Arduino UNO» or «OLIMEXINO STM32» (enlace), being compatible with them. You can click over and has holes to add screw terminals.

Adds the possibility of external 12V or battery power, 3.7V Li-Po battery charger, 3.3V switch-off power supply, 5V or 16V step-up switch-off power supply, RS-485 communications, I2C communications, communications SDI-12, pulse counters, analog reading, programmable battery level reading and joystick interface.

Features

• RS-485 communications
• SDI-12 communications
• I2C bus
• Power Supplies
• Step-Up Power Supply
• LiPo charger
• Interface joystick
• Input counters
• Input analogs

Li-Po Charger MCP73812T-420I/OT:

The MCP73811/2 devices are linear charge management controllers that are designed for use in space limited and cost sensitive applications. The MCP73811/2 provide specific charge algorithms for single cell Li-Ion or Li-Polymer battery to achieve optimal capacity in the shortest charging time possible.

Along with its small physical size, the low number of external components required make the MCP73811/2 ideally suited for portable applications. For applications charging from a USB port, the MCP73811 adheres to all the specifications governing the USB power bus.

The MCP73811/2 employ a constant current/constant voltage charge algorithm. The constant voltage regulation is fixed at 4.20V, with a tight regulation tolerance of 1%. For the MCP73811, the constant current value is selected as 85 mA (low power USB port) or 450 mA (high power USB port) with a digital input signal on the PROG input. For the MCP73812, the constant current value is set with one external resistor. The MCP73811/2 limit the charge current based on die temperature during high power or high ambient conditions. This thermal regulation optimizes the charge cycle time while maintaining device reliability.

The MCP73811/2 are fully specified over the ambient temperature range of -40°C to +85°C. The MCP73811/2 are available in a 5-Lead, SOT-23 package.

Features

• Complete Linear Charge Management Controller
  • Integrated Pass Transistor
  • Integrated Current Sense
  • Integrated Reverse Discharge Protection
• Constant Current / Constant Voltage Operation with Thermal Regulation
  •
• High Accuracy Preset Voltage Regulation: + 1%
• Voltage Regulation: 4.20V
• Selectable Charge Current:
  • MCP73811: 85 mA / 450 mA
• Programmable Charge Current:
  • MCP73812: 50 mA – 500 mA
• Minimum External Components Required:
  • MCP73811: 2 Ceramic Capacitors
  • MCP73812: 2 Ceramic Capacitors and 1 Resistor
• No Preconditioning
• External End-of-Charge Control
• Automatic Power-Down when Input Power Removed
• Active High Charge Enable
• Temperature Range:
  • -40°C to +85°C
• Packaging:
  • 5-Lead SOT-23

STEP-UP SC4503:

The SC4503 is a 1.3MHz current-mode step-up switching regulator with an integrated 1.4A power transistor.

Its high switching frequency allows the use of tiny surface-mount external passive components. The SC4503 features a combined shutdown and soft-start pin. The optional soft-start function eliminates high input current and output overshoot during start-up. The internal compensation network accommodates a wide range of voltage conversion ratios.

The internal switch is rated at 34V making the device suitable for high voltage applications such as Boost and SEPIC.

Features

• Low Saturation Voltage Switch: 260mV at 1.4A
• 1.3MHz Constant Switching Frequency
• Peak Current-mode Control
• Internal Compensation
• Programmable Soft-Start
• Input Voltage Range From 2.5V to 20V
• Output Voltage up to 27V
• Uses Small Inductors and Ceramic Capacitors
• Low Shutdown Current (< 1μA)

RS-485 SN75HVD08:

The SN75HVD08 combines a 3-state differential line driver and differential line receiver designed for balanced data transmission and interoperation with ANSI TIA/EIA-485-A and ISO-8482E standard-compliant devices.
The wide supply voltage range and low quiescent current requirements allow the SN75HVD08s to operate from a 5-V power bus in the cable with as much as a 2-V line voltage drop. Busing power in the cable can alleviate the need for isolated power to be generated at each connection of a ground-isolated bus.

The driver differential outputs and receiver differential inputs connect internally to form a differential input/output (I/O) bus port that is designed to offer minimum loading to the bus whenever the driver is disabled or not powered. The drivers and receivers have active-high and active-low enables respectively, which can be externally connected together to function as a direction control.

Features

• Operates With a 3-V to 5.5-V Supply
• Consumes Less Than 90-mW Quiescent Power
• Open-Circuit, Short-Circuit, and Idle-Bus Failsafe Receiver
• 1/8th Unit-Load (up to 256 nodes on the bus)
• Bus-Pin ESD Protection Exceeds 16-kV HBM
• Driver Output Voltage Slew-Rate Limited for Optimum Signal Quality at 10 Mbps
• Electrically Compatible With ANSI TIA/EIA-485 Standard