MPX4250DP (Searched)
 

Just recived my bundle of samples for my custom Getho ECU.

What I have is the MPX4250DP
The DP stands for Dual Port.
THe data sheet shows the two ports as one for vacum and one for presue. But the Vout table only shows presure vs voltage.

So the doubt I had is how do I measure vacum.
The idea is to control water injection, fuel injection, ign timing and BOV with output from the map sensor.

A bit confused about how to hook up the DP Map sensor and how it works.
It has been sugested leave one tube open to air. Any other ideas.


Thanks

Re: MPX4250DP (Searched)
 

sounds like a dual port version of the map sensor used on the Megasquirt.

Should have just bought an MS component kit, then added the daughtercard, with that you can control a bunch of different things, from shift light, to boost control solenoid, waterinjection, temperature regulated IC cooling fan or squirters, water injection, ...the list goes on, and the engagement parameters can be just about anything from air temp. to manifold pressure, coolant temp, RPM etc.

The sensor is 250KPa or 2.5 Bar, which is 1 Bar vacuum + 1.5 Bar boost or 14.7 psi vacuum + 21.4 psi boost. The output from the sensor is linear, so anything from 0-100 is vacuum, from 100-250 is pressure. Atmosphere is usually around 100 which is approx. what the sensor should read when the engine is not running, or is open to atmosphere. Here's the voltage output with relation to pressure courtesy of my MS setup files, (12t-100t is vacuum, 101t-253t is boost just experiment with the ports til you get a similar output);

KPAFACTOR: ; KPA ADC Volts (* = out of sensor range)
DB 100T ; 0 - 0.000*
DB 100T ; 1 - 0.020*
DB 100T ; 2 - 0.039*
DB 12T ; 3 - 0.059
DB 13T ; 4 - 0.078
DB 14T ; 5 - 0.098
DB 15T ; 6 - 0.118
DB 16T ; 7 - 0.137
DB 17T ; 8 - 0.157
DB 18T ; 9 - 0.176
DB 19T ; 10 - 0.196
DB 20T ; 11 - 0.216
DB 21T ; 12 - 0.235
DB 22T ; 13 - 0.255
DB 23T ; 14 - 0.275
DB 24T ; 15 - 0.294
DB 25T ; 16 - 0.314
DB 26T ; 17 - 0.333
DB 27T ; 18 - 0.353
DB 28T ; 19 - 0.373
DB 29T ; 20 - 0.392
DB 30T ; 21 - 0.412
DB 31T ; 22 - 0.431
DB 32T ; 23 - 0.451
DB 33T ; 24 - 0.471
DB 34T ; 25 - 0.490
DB 34T ; 26 - 0.510
DB 35T ; 27 - 0.529
DB 36T ; 28 - 0.549
DB 37T ; 29 - 0.569
DB 38T ; 30 - 0.588
DB 39T ; 31 - 0.608
DB 40T ; 32 - 0.627
DB 41T ; 33 - 0.647
DB 42T ; 34 - 0.667
DB 43T ; 35 - 0.686
DB 44T ; 36 - 0.706
DB 45T ; 37 - 0.725
DB 46T ; 38 - 0.745
DB 47T ; 39 - 0.765
DB 48T ; 40 - 0.784
DB 49T ; 41 - 0.804
DB 50T ; 42 - 0.824
DB 51T ; 43 - 0.843
DB 52T ; 44 - 0.863
DB 53T ; 45 - 0.882
DB 54T ; 46 - 0.902
DB 55T ; 47 - 0.922
DB 56T ; 48 - 0.941
DB 57T ; 49 - 0.961
DB 58T ; 50 - 0.980
DB 59T ; 51 - 1.000
DB 59T ; 52 - 1.020
DB 60T ; 53 - 1.039
DB 61T ; 54 - 1.059
DB 62T ; 55 - 1.078
DB 63T ; 56 - 1.098
DB 64T ; 57 - 1.118
DB 65T ; 58 - 1.137
DB 66T ; 59 - 1.157
DB 67T ; 60 - 1.176
DB 68T ; 61 - 1.196
DB 69T ; 62 - 1.216
DB 70T ; 63 - 1.235
DB 71T ; 64 - 1.255
DB 72T ; 65 - 1.275
DB 73T ; 66 - 1.294
DB 74T ; 67 - 1.314
DB 75T ; 68 - 1.333
DB 76T ; 69 - 1.353
DB 77T ; 70 - 1.373
DB 78T ; 71 - 1.392
DB 79T ; 72 - 1.412
DB 80T ; 73 - 1.431
DB 81T ; 74 - 1.451
DB 82T ; 75 - 1.471
DB 83T ; 76 - 1.490
DB 84T ; 77 - 1.510
DB 84T ; 78 - 1.529
DB 85T ; 79 - 1.549
DB 86T ; 80 - 1.569
DB 87T ; 81 - 1.588
DB 88T ; 82 - 1.608
DB 89T ; 83 - 1.627
DB 90T ; 84 - 1.647
DB 91T ; 85 - 1.667
DB 92T ; 86 - 1.686
DB 93T ; 87 - 1.706
DB 94T ; 88 - 1.725
DB 95T ; 89 - 1.745
DB 96T ; 90 - 1.765
DB 97T ; 91 - 1.784
DB 98T ; 92 - 1.804
DB 99T ; 93 - 1.824
DB 100T ; 94 - 1.843
DB 101T ; 95 - 1.863
DB 102T ; 96 - 1.882
DB 103T ; 97 - 1.902
DB 104T ; 98 - 1.922
DB 105T ; 99 - 1.941
DB 106T ; 100 - 1.961
DB 107T ; 101 - 1.980
DB 108T ; 102 - 2.000
DB 109T ; 103 - 2.020
DB 109T ; 104 - 2.039
DB 110T ; 105 - 2.059
DB 111T ; 106 - 2.078
DB 112T ; 107 - 2.098
DB 113T ; 108 - 2.118
DB 114T ; 109 - 2.137
DB 115T ; 110 - 2.157
DB 116T ; 111 - 2.176
DB 117T ; 112 - 2.196
DB 118T ; 113 - 2.216
DB 119T ; 114 - 2.235
DB 120T ; 115 - 2.255
DB 121T ; 116 - 2.275
DB 122T ; 117 - 2.294
DB 123T ; 118 - 2.314
DB 124T ; 119 - 2.333
DB 125T ; 120 - 2.353
DB 126T ; 121 - 2.373
DB 127T ; 122 - 2.392
DB 128T ; 123 - 2.412
DB 129T ; 124 - 2.431
DB 130T ; 125 - 2.451
DB 131T ; 126 - 2.471
DB 132T ; 127 - 2.490
DB 133T ; 128 - 2.510
DB 133T ; 129 - 2.529
DB 134T ; 130 - 2.549
DB 135T ; 131 - 2.569
DB 136T ; 132 - 2.588
DB 137T ; 133 - 2.608
DB 138T ; 134 - 2.627
DB 139T ; 135 - 2.647
DB 140T ; 136 - 2.667
DB 141T ; 137 - 2.686
DB 142T ; 138 - 2.706
DB 143T ; 139 - 2.725
DB 144T ; 140 - 2.745
DB 145T ; 141 - 2.765
DB 146T ; 142 - 2.784
DB 147T ; 143 - 2.804
DB 148T ; 144 - 2.824
DB 149T ; 145 - 2.843
DB 150T ; 146 - 2.863
DB 151T ; 147 - 2.882
DB 152T ; 148 - 2.902
DB 153T ; 149 - 2.922
DB 154T ; 150 - 2.941
DB 155T ; 151 - 2.961
DB 156T ; 152 - 2.980
DB 157T ; 153 - 3.000
DB 158T ; 154 - 3.020
DB 158T ; 155 - 3.039
DB 159T ; 156 - 3.059
DB 160T ; 157 - 3.078
DB 161T ; 158 - 3.098
DB 162T ; 159 - 3.118
DB 163T ; 160 - 3.137
DB 164T ; 161 - 3.157
DB 165T ; 162 - 3.176
DB 166T ; 163 - 3.196
DB 167T ; 164 - 3.216
DB 168T ; 165 - 3.235
DB 169T ; 166 - 3.255
DB 170T ; 167 - 3.275
DB 171T ; 168 - 3.294
DB 172T ; 169 - 3.314
DB 173T ; 170 - 3.333
DB 174T ; 171 - 3.353
DB 175T ; 172 - 3.373
DB 176T ; 173 - 3.392
DB 177T ; 174 - 3.412
DB 178T ; 175 - 3.431
DB 179T ; 176 - 3.451
DB 180T ; 177 - 3.471
DB 181T ; 178 - 3.490
DB 182T ; 179 - 3.510
DB 183T ; 180 - 3.529
DB 183T ; 181 - 3.549
DB 184T ; 182 - 3.569
DB 185T ; 183 - 3.588
DB 186T ; 184 - 3.608
DB 187T ; 185 - 3.627
DB 188T ; 186 - 3.647
DB 189T ; 187 - 3.667
DB 190T ; 188 - 3.686
DB 191T ; 189 - 3.706
DB 192T ; 190 - 3.725
DB 193T ; 191 - 3.745
DB 194T ; 192 - 3.765
DB 195T ; 193 - 3.784
DB 196T ; 194 - 3.804
DB 197T ; 195 - 3.824
DB 198T ; 196 - 3.843
DB 199T ; 197 - 3.863
DB 200T ; 198 - 3.882
DB 201T ; 199 - 3.902
DB 202T ; 200 - 3.922
DB 203T ; 201 - 3.941
DB 204T ; 202 - 3.961
DB 205T ; 203 - 3.980
DB 206T ; 204 - 4.000
DB 207T ; 205 - 4.020
DB 208T ; 206 - 4.039
DB 208T ; 207 - 4.059
DB 209T ; 208 - 4.078
DB 210T ; 209 - 4.098
DB 211T ; 210 - 4.118
DB 212T ; 211 - 4.137
DB 213T ; 212 - 4.157
DB 214T ; 213 - 4.176
DB 215T ; 214 - 4.196
DB 216T ; 215 - 4.216
DB 217T ; 216 - 4.235
DB 218T ; 217 - 4.255
DB 219T ; 218 - 4.275
DB 220T ; 219 - 4.294
DB 221T ; 220 - 4.314
DB 222T ; 221 - 4.333
DB 223T ; 222 - 4.353
DB 224T ; 223 - 4.373
DB 225T ; 224 - 4.392
DB 226T ; 225 - 4.412
DB 227T ; 226 - 4.431
DB 228T ; 227 - 4.451
DB 229T ; 228 - 4.471
DB 230T ; 229 - 4.490
DB 231T ; 230 - 4.510
DB 232T ; 231 - 4.529
DB 232T ; 232 - 4.549
DB 233T ; 233 - 4.569
DB 234T ; 234 - 4.588
DB 235T ; 235 - 4.608
DB 236T ; 236 - 4.627
DB 237T ; 237 - 4.647
DB 238T ; 238 - 4.667
DB 239T ; 239 - 4.686
DB 240T ; 240 - 4.706
DB 241T ; 241 - 4.725
DB 242T ; 242 - 4.745
DB 243T ; 243 - 4.765
DB 244T ; 244 - 4.784
DB 245T ; 245 - 4.804
DB 246T ; 246 - 4.824
DB 247T ; 247 - 4.843
DB 248T ; 248 - 4.863
DB 249T ; 249 - 4.882
DB 250T ; 250 - 4.902
DB 251T ; 251 - 4.922
DB 252T ; 252 - 4.941
DB 253T ; 253 - 4.961
DB 100T ; 254 - 4.980*
DB 100T ; 255 - 5.000*

Good luck!

Neil

Re: MPX4250DP (Searched)
 

Ive just had lousy luck trying to use other guys circuits. We eat breathe and ---- Pic Micros. As we design ECUs for Bikes have been doing it for lats 6 years.
I realized my question a stupid one when I looked at the X-Axis on the Graph. But thanks for clearing it up.
We just recived 3 single Port Sensors also They are called the MPX4250AP vs DP.
The problem is all the Mega squirt stuff is priced in dollars and we pay 300% import duty on anything from outside the country.
Also if we come up with something on our own we can market it. Our completelly built ECUs with hand held programer typically sells for less than the MS.
To cut a long story short. Im a cheap poor bastard lol.
Who likes to keep trying to reinventing the wheel.
Ps: The MS effort rocks. Wish they had something like it 6 years ago.