LDO Click Board™

Product Code: MIKROE-5645

How Does The LDO Click Board™ Work? The LDO Click Board™ is based on the TPS7A83A, a high-current (2A), low-noise, high-accuracy, and low-dropout linear voltage regulator from Texas Instruments. The TPS7A83A has several features that make it useful in various applications, like high accuracy, high-PSR output, and fast transient response for voltage regulation part, as well as certain internal protections like thermal shutdown and foldback current limit. All these features make this Click board™ a robust solution for many challenging problems in generating a clean, accurate power supply. The TPS7A8300A can be easily enabled using the EN pin of the mikroBUS™ socket, offering a switch operation to turn ON/OFF the TPS7A8300A. It has a pin-programmable output voltage from 0.8V-3.95V with a 50mV resolution, or it can be adjustable from 0.8V-5.2V using an external resistor divider (R9 and R10). The pin-programmable output voltage is possible thanks to the TCA9534A, an I2C-configurable I/O expander also from Texas Instruments, which by setting the appropriate voltage setting pins on the TPS7A83A, which are connected to an internal feedback network, programs the regulated output voltage.

The TCA9534A expander also can choose the least significant bit (LSB) of its I2C slave address by positioning SMD jumpers labelled as ADDR SEL to an appropriate position marked as 0 and 1. The adjustable output voltage is achieved through voltage divider resistors whose corresponding values can be found in the datasheet table. One of the power terminals on the board is the VBIAS terminal, which minimizes the internal charge-pump noise when the internal voltage is clamped, thereby reducing the overall output noise floor. This rail enables the use of low-input voltage, low-output (LILO) voltage conditions (VEXT=1.2V, VOUT =1V) to reduce the power dissipation of the TPS7A8300A. Using a VBIAS voltage improves DC and AC performance for VEXT≤2.2V. The LDO Click Board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC SEL jumper. This way, it is allowed for both 3.3V and 5V capable MCUs to use the communication lines properly. Additionally, there is a possibility for the TPS7A83A power supply selection via jumper labelled as VIN SEL to supply the TPS7A83A from an external power supply terminal in the range from 1.1V to 6.5V or with selected mikroBUS™ power rail. However, the Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used, as a reference, for further development. SPECIFICATIONS Type Buck, Linear Applications It can be used to power noise-sensitive components such as serializers and deserializer, ADCs, DACs, and RF components On-board modules TPS7A83A - low-dropout linear regulator from Texas Instruments Key Features High accuracy, low output voltage noise, wide input voltage range, pin-programmable and adjustable output voltage, excellent load transient response, bias supply to improve performance, and more Interface I2C Compatibility mikroBUS Click board size L (57.15 x 25.4 mm) Input Voltage 3.3V or 5V PINOUT DIAGRAM This table shows how the pinout of the LDO Click Board™ corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns). Notes Pin Pin Notes NC 1 AN PWM 16 NC NC 2 RST INT 15 NC Enable EN 3 CS RX 14 NC NC 4 SCK TX 13 NC NC 5 MISO SCL 12 SCL I2C Clock NC 6 MOSI SDA 11 SDA I2C Data Power Supply 3.3V 7 3.3V 5V 10 5V Power Supply Ground GND 8 GND GND 9 GND Ground ONBOARD SETTINGS AND INDICATORS Label Name Default Description LD1 PWR - Power LED Indic