Sitime

Example Decoding

SiT1533AI-H4-18E-32.768000X
│   │   │   │   │    │     │
│   │   │   │   │    │     └── X = Output type suffix
│   │   │   │   │    └── 32.768000 = Frequency (32.768 kHz)
│   │   │   │   └── 18E = 1.6x1.2mm package (1612 size)
│   │   │   └── H4 = Voltage/configuration code
│   │   └── AI = Temperature grade A, option I
│   └── 1533 = MHz LVCMOS Oscillator series
└── SiT = SiTime prefix

SiT8021AC-82-33S-24.000000X
│   │    │   │   │    │     │
│   │    │   │   │    │     └── X = Output type suffix
│   │    │   │   │    └── 24.000000 = 24 MHz
│   │    │   │   └── 33S = 3.2x2.5mm SOIC variant
│   │    │   └── 82 = Voltage/configuration
│   │    └── AC = Temperature grade A, variant C
│   └── 8021 = Precision MHz Oscillator
└── SiT = SiTime prefix

Product Families

SiT15xx - MHz LVCMOS Oscillators

SiT16xx - Low Power Oscillators

SiT17xx - Ultra Low Power

SiT5xxx/SiT85xx - Super-TCXO

SiT80xx - Precision MHz Oscillators

SiT81xx - Differential Oscillators

SiT86xx - High Performance

SiT88xx - Network Sync

SiT90xx - High Temperature

SiT91xx - Automotive AEC-Q100

SiT93xx - Clock Generators

SiT95xx - High Performance Clock

Package Codes

Numeric Size Codes

Chip-Scale Packages

Other Packages

Temperature Grades

Temperature grades are typically indicated in the first segment after the family number:

Examples:

• SiT1533AI - Grade A, Industrial option
• SiT8021BC - Grade B, Extended

Voltage/Configuration Codes

The second segment (after temperature) often contains voltage and configuration info:

Note: These codes vary by product family - consult SiTime datasheets for specific mappings.

Frequency Encoding

Frequency appears as the last numeric segment before any output type suffix:

Common Frequencies

Output Type Suffixes

Component Types in Handler

The SiTimeHandler supports:

Note: 32.768 kHz MEMS oscillators can serve as drop-in replacements for quartz crystals, hence the CRYSTAL type registration for those frequencies.

Handler Implementation Notes

Series Extraction

// Series is extracted as "SiT" + first 2 digits of 4-digit family
// Example: SiT1533AI-H4-18E-32.768000X -> "SiT15"
// Example: SiT8021AC-82-33S-24.000000X -> "SiT80"

// Special case: SiT5xxx Super-TCXO series
// SiT5155 -> "SiT5" (not "SiT51")
if (upperMpn.startsWith("SIT5") && Character.isDigit(upperMpn.charAt(4))) {
    return "SiT5";
}

Package Extraction

// Package code is typically the third hyphen-separated segment
// SiT1533AI-H4-18E-32.768000X
//              ^^^
// Pattern: -([0-9]{2}[A-Z]|[A-Z]{2,3})-

Frequency Extraction

// Frequency is the last segment after the final hyphen
// SiT1533AI-H4-18E-32.768000X
//                  ^^^^^^^^^^
// Pattern: ([0-9]+(?:\.[0-9]+)?)[MKX]?$

Official Replacement Logic

Two SiTime parts can be replacements if:

1. Same series (e.g., both SiT15)
2. Same frequency

They may differ in:

• Temperature grade
• Package size
• Voltage configuration

Example MPNs

Crystal Replacement Use Case

SiTime 32.768 kHz oscillators are often used as drop-in replacements for traditional quartz crystals in RTC applications:

Traditional Crystal Circuit:

[MCU] --XTAL1-- [Crystal] --XTAL2-- [MCU]
                   |
                 [Caps]

SiTime MEMS Replacement:

[MCU] --OSC_IN-- [SiT1533] --VDD-- [Power]
                     |
                   [GND]

Advantages of MEMS replacement:

• No external load capacitors needed
• Better shock/vibration resistance
• Faster startup time
• More consistent frequency across temperature

Related Files

• Handler: manufacturers/SiTimeHandler.java
• Component types: OSCILLATOR, CRYSTAL, IC
• Series descriptions: Available via getSeriesDescription(mpn) helper method

Learnings & Edge Cases

• SiT5 vs SiT85: Both refer to Super-TCXO family. SiT5xxx and SiT85xx patterns are both registered.
• Frequency parsing: Frequency appears after the last hyphen, before optional output suffix (X, M, K).
• 32.768 kHz special case: These parts are registered as both OSCILLATOR and CRYSTAL types since they can replace quartz crystals.
• Package code position: The package code is in the third hyphen-separated segment, not a suffix like many other manufacturers.
• No manufacturer-specific ComponentTypes: SiTimeHandler uses generic types (OSCILLATOR, CRYSTAL, IC) rather than SiTime-specific types.
• Case insensitivity: Handler converts MPNs to uppercase before pattern matching (SiT = SIT = sit).
• Series extraction returns 2-digit: Unlike some handlers that return full part numbers, SiTime series extraction returns abbreviated form (e.g., "SiT15" not "SiT1533").