Today I want to talk about a new breakout board that I made:
It is based on TPS62740, an ultra low power step down switching regulator that can regulate input voltage from 2.2V to 5.5V to an output voltage from 1.8V to 3.3V and a maximum of 300mA output current, in fact it is designed for battery powered system that handle low current and where energy saving is a must.
It is a switching regulator so the efficiency is very high:
It can perform up to 90% of efficiency with only 10µA of output current; at higher current it perform even better.
its main features are:
- Input voltage from 2.2V to 5.5V
- Ultra low quiescent current of 360 nA
- Very high efficiency
- 16 selectable outputs choosen by 4 inputs that performs output from 1.8V to 3.3V with 0.1V steps
- Output current up to 300mA
Here a table that explain how to choose the desired output voltage:
VSEL input voltage must be between 2.2V and VIN voltage, however the high level input threeshold is set to 1.1V and the low level input threeshold is set to 0.4V so in a typical application where VIN is about 5V, you can set VSEL pins with a 3V3 or a 5V source like for example pins of a microcontroller.
Before explain the pinout of my brekout board, take a look at the schematic:
here the pinout:
- GND: connect these 2 pins to the GND of your entire system
- VOUT: Output regulated voltage, it can assume value between 1.8V to 3.3V
- LOAD: with CTRL “HIGH”, an internal load switch connects the LOAD pin to the VOUT pin. if not used leave it open.
- CTRL: This pin controls the output LOAD pin. With CTRL “LOW”, the output LOAD is disabled. This pin must be terminated.
- VIN: Input voltage: connect here the unregulated voltage that you want to regulate, it value must be between 2.2V to 5.5V
- EN: an “HIGH” state on this pin enable the device, a “LOW” state turn the device into shutdown mode. This pin must be terminated.
- VSEL1, VSEL2, VSEL3, VSEL4 are the output voltage selection pins, follow the table that I posted above or see page 4 of TPS62740 datasheet to choose your desired output voltage.
- PG: pulled-up power good pin, it indicate that the “power is good” so:
- you will read “HIGH” if VIN is above VTH_UVLO+ (that is about 2V) and EN is HIGH
- you will read “LOW” if VIN is below VTH_UVLO- (that is about 2V) or EN is LOW
This breakout board offer a valid option when used in battery powered systems, it consumption is very low and give you the possibility to choose a different output voltage every time you want using only 4 pins
In the next articles I’ll show you some hardware details of this board and also how to use it in different ways