RAK16001 WisBlock ADC Module Datasheet

Overview

Description

The RAK16001 is an Analog-to-Digital (ADC) module, which uses an ADS7830 from Texas Instruments that can measure 8-independent voltages or 4-independent differential voltages. The ADS7830 is an 8-bit ADC module that features a serial I2C interface and an 8-channel multiplexer with one sample-and-hold amplifier circuit.

Features

• ADC Module: 8 Single-ended Inputs or 4 Differential Inputs
• 70 kHz Sampling Rate
• ±0.5 LSB INL/DNL
• 8 Bits no missing codes
• 3.3 V Power supply
• Internal voltage reference at 2.5 V
• Chipset: Texas Instruments ADS7830
• Module size: 25 X 45 mm

Specifications

Overview

Mounting

The RAK16001 module can be mounted on the IO slot of the WisBlock Base board. Figure 1 shows the mounting mechanism of the RAK16001 on a WisBlock Base module, such as the RAK5005-O.

Figure 1: RAK16001 mounting mechanism on a WisBlock Base module

Hardware

The hardware specification is categorized into four parts. It discusses the pinouts and their corresponding functions and diagrams of the module. It also covers the electrical and mechanical characteristics that include the tabular data of the functionalities and standard values of the RAK16001 WisBlock ADC Module.

Chipset

Vendor	Part number
Texas Instruments	ADS7830

Pin Definition

The RAK16001 module has a 40-pin WisConnector that is compatible to the WisBlock Base IO Slot. The pin order of the connector and the pinout definition is shown in Figure 2.

Figure 2: RAK16001 Pinout Diagram

NOTE

• Only I2C related pins, 3V3_S and GND are connected to the WisConnector of this module.
• 3V3_S voltage output from the WisBlock Base that powers the RAK16001 module can be controlled by the WisBlock Core via WB_IO2 (WisBlock IO2 pin). This makes the module ideal for low-power IoT projects since the WisBlock Core can totally disconnect the power of the RAK16001 module.

Electrical Characteristics

This section shows the maximum and minimum ratings of the RAK16001 module and its recommended operating conditions. Refer to the table presented below.

Recommended Operating Conditions

Symbol	Description	Condition	Min.	Nom.	Max.	Unit
3V3_S	VDD	Normal operation	-	3.3	-	V
VREF	ADC Voltage Reference	Normal operation	-	2.5	-	V
U1	Full-Scale Input Scan	Positive Input – Negative Input	0	-	VREF	V
U2	Absolute Input Range	Positive Input	–0.2	-	VDD+0.2	V
U3	Absolute Input Range	Negative Input	–0.2	-	+0.2	V

Mechanical Characteristic

Board Dimensions

The mechanical dimensions of the RAK16001 module are shown in Figure 3 below.

Figure 3: RAK16001 Mechanical Dimensions

WisConnector PCB Layout

Figure 4: WisConnector PCB footprint and recommendations

PCB Silkscreen

Figure 5: RAK16001 PCB Silkscreen

Schematic Diagram

Figure 6 shows the schematic of the RAK16001 module.

Figure 6: RAK16001 WisBlock Module Schematics

ADC Voltage Reference

Figure 7 shows the reference voltage of 3 V.

Figure 7: RAK16001 ADC Voltage Reference

ADC Converter

Figure 8: RAK16001 ADC Converter

NOTE

• R3-R20 are built for the voltage divider resistors that can expand the measure range. By default, this feature is disabled and not used. If you want to have input more than 3.3 V, change the value of these resistors.

I2C Device Address Select

You can change the I2C slave address. By default, the 7-bit I2C address is 0x48.

Figure 9: RAK16001 I2C Address Select

I2C Pull-Up Resistance

Figure 10: RAK16001 I2C Pull-up Resistance

NOTE

• The built-in I2C pull-up resistors are on the WisBlock Base module and not on the RAK16001.