Weather Balloon Pressure Sensor

I am currently building a weather balloon payload that will need to collect air samples at specific altitudes which will be determined using some kind of a pressure sensor (currently using the SCP1000). I just realized that its range is only 30 kPa - 120kPa, meaning it will only be functional up to around 30,000 ft. For my application I need the sensor to be operational up to around 100,000 feet, and need it to be as small and light as possible. Does anyone have a recommendation for a good sensor for this kind of application?

Thanks, Lance Kifer

DigiKey has 6 DIP/SMD sensors from Honeywell that measure 0-1 or 0-1.6 bar. There are I2C and SPI models as well as analog.

Unfortunately they cose $28 to $30 each and you have to buy at least 25 if you want them from DigiKey. Perhaps another distributor will have them in single quantities. Series name is "TruStability"

HSCDANN001BA2A3, 3.3V DIP, 0 ~ 1 bar, I²C HSCMANN001BA2A3, 3.3V SMD, 0 ~ 1 bar, I²C HSCMAND001BAAA5, 5V SMD, 0 ~ 1 bar, ANALOG HSCMRNN1.6BASA3, 3.3V SMD, 0 ~ 1.6 bar, SPI HSCMAND001BAAA5, 5V SMD, 0 ~ 1 bar, ANALOG HSCMRND001BA2A5, 5V SMD, 0 ~ 1 bar, I²C

I seem to recall from another recent thread on this topic that civilian GPS units don't operate over 60,000 ft, to avoid being classified as munitions by the US government. Still nice to have position data during some of the flight though. Might also be able to use it on the way up to calibrate the pressure sensor.

You can get a GPS engine to operate above 60000 ft but you'll have to have the manufacturer program a custom BIOS for the engine. They'll need to leave the speed limiter in place to make the device legal. So as long as your balloon isn't traveling faster than 1151 mph it's doable.

Freescale has some nice pressure sensors like this one:

There are models that read 0 .. 1 BAR absolute and output 0 .. 4.5V analogue signal that would make decent altimeters for an Arduino. They're priced at around $12 on Mouser. Weight is well under a gram. Power required is under 35 mW.

We have built a number of high altitude balloons / payloads.

We use this GPS receiver.... only $38.00 USD

Works at all altitudes.


A list of GPS receivers that work over 60k’: W0RPK GPSv60KFT

We use the Garmin GPS18.

Most of the freescale pressure sensors, even those that say their low end is 0 PSI, do not read down to 0 PSI. Most of them will top out around 50k’.

Read datasheets carefully for the actual definition of 0 PSI; it usually is not 0.

An experienced ballooner recommended the Honeywell ASDX015A24R. He’s used it and it worked well up to 100k’. US$80 each at Mouser, though.


The ASDX015A24R is $102.21 at but Newark shows this as a viable substitute:

Honeywell ASDXACX015PAAA5 $33.15

Looks like the same thing but with a snout. $31.93 at DigiKey. The SPI version is slightly cheaper at DigiKey but they don't stock them so you have to buy 25.

Mouser has the SPI version (ASDXACX015PA2A5) for 33.15 in single quantities. Currently 16 in stock.