Cantara/sensirion

Sensirion Manufacturer Skill

Manufacturer Overview

Sensirion AG is a Swiss sensor manufacturer specializing in environmental sensors. Their product families include:

| Family | Products | Application | |--------|----------|-------------| | SHTxx | SHT30, SHT31, SHT35, SHT40, SHT41, SHT45, SHT85 | Humidity & Temperature | | STSxx | STS30, STS31, STS40 | Temperature only | | SGPxx | SGP30, SGP40, SGP41 | VOC/Gas (Air Quality) | | SCDxx | SCD30, SCD40, SCD41 | CO2 concentration | | SFAxx | SFA30 | Formaldehyde detection | | SPSxx | SPS30 | Particulate matter (PM1.0/2.5/10) | | SLFxxxx | SLF3S-1300F | Liquid flow measurement | | SDPxxx | SDP31, SDP810 | Differential pressure |

All Sensirion sensors use I2C digital interface (some variants support alternate addresses).

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MPN Structure

Sensirion MPNs follow this general structure:

[PREFIX][SERIES]-[VARIANT][GRADE]-[REEL]
   │       │        │        │       │
   │       │        │        │       └── Reel option: R2, R4 (tape & reel qty)
   │       │        │        └── Accuracy grade: A, B, F
   │       │        └── Variant code: DIS, AD1B, D, P, etc.
   │       └── Series number (30, 31, 40, 41, 45, etc.)
   └── Family prefix (SHT, STS, SGP, SCD, SFA, SPS, SLF, SDP)

Example Decoding

SHT31-DIS-B
│  │  │   │
│  │  │   └── B = Accuracy grade B
│  │  └── DIS = Digital sensor variant
│  └── 31 = Series 31 (mid-range accuracy)
└── SHT = Humidity & Temperature sensor

SHT40-AD1B-R2
│  │  │  │ │
│  │  │  │ └── R2 = Tape & reel (2000 pcs)
│  │  │  └── B = Accuracy grade B
│  │  └── AD1 = Alternate I2C address variant
│  └── 40 = Series 40 (4th generation)
└── SHT = Humidity & Temperature sensor

SGP40-D-R4
│  │  │ │
│  │  │ └── R4 = Tape & reel (4000 pcs)
│  │  └── D = Standard digital variant
│  └── 40 = Series 40
└── SGP = Gas sensor (VOC)

SLF3S-1300F
│  │  │   │
│  │  │   └── F = Variant identifier
│  │  └── 1300 = Flow range identifier
│  └── 3S = Series/size
└── SLF = Liquid Flow sensor

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Variant Codes

Package/Variant Codes

| Code | Description | Package | |------|-------------|---------| | DIS | Digital sensor (standard) | DFN | | DIS-B | Digital sensor, B grade | DFN | | ARP | ARP variant | DFN | | AD1B | Alternate I2C address, B grade | DFN | | AD1F | Alternate I2C address, F grade | DFN | | BD1B | B variant, alternate address | DFN | | D | Standard digital | DFN | | P | Pin header (development kit) | PIN | | B | B accuracy grade | DFN | | F | F accuracy grade | DFN |

Reel Options

| Code | Description | |------|-------------| | R2 | Tape & reel, 2000 pieces | | R4 | Tape & reel, 4000 pieces |

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Accuracy Grades

Sensirion sensors come in different accuracy grades. Higher accuracy = tighter tolerance.

| Grade | Accuracy Level | Typical RH Tolerance | Use Case | |-------|---------------|---------------------|----------| | A | Highest | +/- 1.5% RH | Precision applications | | B | Mid-range | +/- 2.0% RH | General purpose | | F | Standard | +/- 2.5% RH | Cost-sensitive |

Grade Ordering (best to worst): A > B > F

Compatibility Rule: Higher accuracy grades can replace lower grades (A can replace B, B can replace F).

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Series Families

SHT Humidity & Temperature Sensors

| Series | Generation | Key Features | |--------|------------|--------------| | SHT3x | 3rd gen | SHT30/31/35 - established, wide use | | SHT4x | 4th gen | SHT40/41/45 - smaller, lower power | | SHT8x | Premium | SHT85 - high accuracy, PTFE filter |

Compatibility: SHT4x can replace SHT3x (next generation, same function).

Within series: SHT35 > SHT31 > SHT30 (accuracy ordering)

STS Temperature-Only Sensors

| Series | Generation | Notes | |--------|------------|-------| | STS3x | 3rd gen | STS30/31 - temperature only | | STS4x | 4th gen | STS40 - smaller footprint |

Compatibility: STS4x can replace STS3x.

SGP Gas Sensors (VOC)

| Series | Generation | Key Features | |--------|------------|--------------| | SGP3x | 3rd gen | SGP30 - multi-pixel gas sensor | | SGP4x | 4th gen | SGP40/41 - improved, lower power |

Compatibility: SGP4x can replace SGP3x (improved performance).

SCD CO2 Sensors

| Series | Generation | Key Features | |--------|------------|--------------| | SCD3x | NDIR based | SCD30 - photoacoustic, larger size | | SCD4x | Miniaturized | SCD40/41 - smaller, breakout board compatible |

Compatibility: SCD4x can replace SCD3x (miniaturized, same accuracy).

SDP Differential Pressure Sensors

| Series | Pressure Range | Notes | |--------|---------------|-------| | SDP3x | +/- 500 Pa | SDP31 - low range | | SDP8x | +/- 500/1000 Pa | SDP810 - extended range |

Not interchangeable - different pressure ranges require design consideration.

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Supported Component Types

From SensirionHandler.getSupportedTypes():

Set.of(
    ComponentType.SENSOR,              // Generic sensor
    ComponentType.HUMIDITY_SENSOR,     // SHTxx, humidity measurement
    ComponentType.TEMPERATURE_SENSOR,  // SHTxx, STSxx temperature
    ComponentType.PRESSURE_SENSOR,     // SDPxx differential pressure
    ComponentType.SENSOR_FLOW,         // SLFxx liquid flow
    ComponentType.IC                   // SGPxx, SCDxx (complex sensors)
)

Pattern Registration

| Component Type | Pattern | Products | |----------------|---------|----------| | HUMIDITY_SENSOR | ^SHT[0-9]{2}.* | SHT30, SHT31, SHT40, etc. | | TEMPERATURE_SENSOR | ^SHT[0-9]{2}.*, ^STS[0-9]{2}.* | SHTxx, STSxx | | SENSOR (gas) | ^SGP[0-9]{2}.* | SGP30, SGP40, SGP41 | | SENSOR (CO2) | ^SCD[0-9]{2}.* | SCD30, SCD40, SCD41 | | SENSOR (formaldehyde) | ^SFA[0-9]{2}.* | SFA30 | | SENSOR (particulate) | ^SPS[0-9]{2}.* | SPS30 | | SENSOR_FLOW | ^SLF[0-9A-Z]+.* | SLF3S-1300F | | PRESSURE_SENSOR | ^SDP[0-9]{2,3}.* | SDP31, SDP810 |

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Package Code Extraction

The handler extracts package codes from the variant portion after the first hyphen:

// Input: SHT31-DIS-B
// After first dash: "DIS-B"
// Package part: "DIS" (before second dash)
// Returns: "DFN" (mapped)

// Input: SHT40-AD1B-R2
// After first dash: "AD1B-R2"
// Package part: "AD1B"
// Returns: "DFN"

Package Code Mappings

| Variant Code | Mapped Package | |--------------|----------------| | DIS | DFN | | DIS-B | DFN | | ARP | DFN | | AD1B | DFN | | AD1F | DFN | | BD1B | DFN | | D | DFN | | P | PIN (development) | | B | DFN | | F | DFN |

Note: Most Sensirion sensors use DFN (Dual Flat No-lead) packaging.

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Series Extraction

The handler extracts series by grouping based on prefix patterns:

// Input: SHT31-DIS-B
// Base part: "SHT31" (before first dash)
// Starts with "SHT3" → Returns: "SHT3x"

// Input: SCD40-D-R2
// Base part: "SCD40"
// Starts with "SCD4" → Returns: "SCD4x"

Series Groupings

| Prefix | Series Group | |--------|--------------| | SHT3x | SHT30, SHT31, SHT35 | | SHT4x | SHT40, SHT41, SHT45 | | SHT8x | SHT85 | | STS3x | STS30, STS31 | | STS4x | STS40 | | SGP3x | SGP30 | | SGP4x | SGP40, SGP41 | | SCD3x | SCD30 | | SCD4x | SCD40, SCD41 | | SFA3x | SFA30 | | SPS3x | SPS30 | | SLFxx | All SLF flow sensors | | SDP3x | SDP31 | | SDP8x | SDP810 |

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Replacement Compatibility

Official Replacement Logic

The handler implements isOfficialReplacement() with these rules:

1. Same series: Compatible if accuracy grade allows

   • A can replace B or F
   • B can replace F
   • F cannot replace A or B

2. Cross-series replacements:

   • SHT4x can replace SHT3x (next generation)
   • STS4x can replace STS3x
   • SGP4x can replace SGP3x (improved gas sensor)
   • SCD4x can replace SCD3x (miniaturized CO2)

3. Not interchangeable:

   • SDP3x and SDP8x (different pressure ranges)
   • Different sensor families (SHT cannot replace SGP)

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Example MPNs

| MPN | Type | Description | |-----|------|-------------| | SHT30-DIS-B | Humidity/Temp | Series 30, digital, grade B | | SHT31-DIS-F | Humidity/Temp | Series 31, digital, grade F | | SHT35-DIS-B | Humidity/Temp | Series 35, digital, grade B (highest accuracy in 3x) | | SHT40-AD1B-R2 | Humidity/Temp | Series 40, alt address, grade B, 2k reel | | SHT41-AD1B-R2 | Humidity/Temp | Series 41, alt address, grade B | | SHT45-AD1B-R2 | Humidity/Temp | Series 45, highest accuracy in 4x | | SHT85 | Humidity/Temp | Premium, PTFE filter membrane | | STS30-DIS-B | Temp only | Temperature-only sensor | | STS40-AD1B-R2 | Temp only | 4th gen temp-only | | SGP30 | Gas/VOC | Multi-pixel gas sensor | | SGP40-D-R4 | Gas/VOC | 4th gen VOC sensor | | SGP41-D-R4 | Gas/VOC | NOx + VOC dual sensor | | SCD30 | CO2 | NDIR CO2 sensor module | | SCD40-D-R2 | CO2 | Miniaturized CO2 sensor | | SCD41-D-R2 | CO2 | Extended range CO2 | | SFA30 | Formaldehyde | Formaldehyde sensor | | SPS30 | Particulate | PM1.0/2.5/4/10 sensor | | SLF3S-1300F | Liquid Flow | 0-40 ml/min flow sensor | | SDP31 | Pressure | +/- 500 Pa differential | | SDP810-500PA | Pressure | Configurable range |

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Handler Implementation Notes

Interface Extraction

// Most Sensirion sensors use I2C
// AD variants indicate alternate I2C address

if (upperMpn.contains("-AD")) return "I2C-ALT"; // Alternate address
return "I2C"; // Default

Accuracy Grade Extraction

// Grade embedded in variant code or as suffix
// SHT31-DIS-B → grade "B"
// SHT40-AD1B → grade "B" (from "1B")

if (upperMpn.contains("-B") || upperMpn.contains("1B")) return "B";
if (upperMpn.contains("-F") || upperMpn.contains("1F")) return "F";
if (upperMpn.contains("-A") || upperMpn.contains("1A")) return "A";

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Related Files

• Handler: manufacturers/SensirionHandler.java
• Component types: SENSOR, HUMIDITY_SENSOR, TEMPERATURE_SENSOR, PRESSURE_SENSOR, SENSOR_FLOW, IC

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Learnings & Quirks

• All sensors use I2C: Sensirion standardizes on I2C digital interface across all product families
• DFN is dominant: Most sensors use DFN (Dual Flat No-lead) packaging; "P" suffix indicates pin header for development
• Generation upgrades: 4x series generally replaces 3x series with improved specs and smaller footprint
• Accuracy grade hierarchy: A > B > F; higher grades can replace lower but not vice versa
• Dual-function sensors: SHTxx measures both humidity AND temperature; use appropriate ComponentType based on application
• Complex sensors as IC: Gas (SGP), CO2 (SCD), and particulate (SPS) sensors are registered as both SENSOR and IC due to their processing complexity
• AD variants: "AD" in variant code indicates alternate I2C address for multi-sensor configurations
• Reel quantities: R2 = 2000 pcs, R4 = 4000 pcs tape and reel
• Pressure sensors not interchangeable: SDP3x and SDP8x have different pressure ranges; check specs before substitution
• No manufacturer-specific ComponentTypes: Unlike TI/ST handlers, Sensirion uses generic types (HUMIDITY_SENSOR, not HUMIDITY_SENSOR_SENSIRION)

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