Vertiv 11205 Hall-Effect Latch Sensor IC
Overview
The Vertiv 11205 is a Hall-effect latch IC designed for magnetic position sensing in demanding electronic environments. Operating across a 2.8 to 5.5 V supply range, the 11205 covers the full span of logic-level rails used in modern embedded designs — from 3.3 V microcontroller systems to 5 V industrial I/O buses — without requiring external regulation.
Packaged in the compact SOT23W or SIP footprint, it fits constrained PCB layouts where a full-size sensor package would not. The operate point of 35 G and release point of 25 G provide a 10 G hysteresis window, which prevents output chatter when a magnet passes near the threshold — a practical advantage in vibration-prone enclosures or assemblies where slight mechanical play is unavoidable.
Key Features
- 2.8–5.5 V Supply Range: Spans both 3.3 V and 5 V logic families, so the same part works across mixed-voltage board designs without a dedicated LDO.
- 10 G Hysteresis (35 G operate / 25 G release): Eliminates output bounce at the switching threshold — important in motors, valve actuators, and door-position sensors where magnets don't traverse cleanly.
- 30 mA Output Current / 50 mV Saturation Voltage: Drives most indicator LEDs and small relay coils directly, reducing BOM count by eliminating a buffer stage.
- 60 mA Output Short-Circuit Current Limit: Protects the device and downstream circuitry during wiring faults without requiring an external current-limiting resistor in most designs.
- -40°C to 150°C Operating Temperature: Qualifies for under-hood automotive, industrial furnace-adjacent, and outdoor control panel deployments where standard commercial-temp parts fail.
- 800 kHz Chopping Frequency: The internal chopper-stabilized architecture cancels offset voltage drift — output accuracy holds across the full temperature range without factory calibration at each operating point.
- 25 µs Power-On Time: The device reaches valid output state within 25 µs of supply stabilization — fast enough for systems that cycle power frequently or use sleep/wake duty cycling.
- 0.2 µs Rise / 0.1 µs Fall Output Transition: Clean switching edges reduce EMI coupling onto adjacent signal lines in high-density PCB layouts.
- 2 mA Supply Current: Minimal quiescent draw makes this viable in battery-backed or energy-harvesting sensor nodes.
Integration & Compatibility
The SOT23W and SIP package options give board designers flexibility: SOT23W suits reflow-soldered SMT assemblies; SIP suits through-hole or hand-soldered prototyping and repair scenarios. With a junction temperature ceiling of 175°C and package thermal resistance values of 228°C/W (LH) and 165°C/W (UA), thermal budget calculations for high-ambient environments should account for self-heating at the 30 mA output load before specifying heat-sink or airflow requirements.
Frequently Asked Questions
Q: What supply voltages does the Vertiv 11205 support?
A: The 11205 operates from 2.8 V to 5.5 V, covering both 3.3 V and 5 V logic-level systems.
Q: What is the switching hysteresis on the 11205?
A: The operate point is 35 G and the release point is 25 G, giving 10 G of hysteresis to prevent output chatter near the switching threshold.
Q: What package options are available for the 11205?
A: The 11205 is available in SOT23W (surface-mount) and SIP (through-hole) packages.
Q: What is the maximum operating temperature for the 11205?
A: The 11205 is rated for operation from -40°C to 150°C, with a junction temperature limit of 175°C.
Q: Can the 11205 drive an LED or small relay directly?
A: Yes — with a 30 mA output current rating and 50 mV output saturation voltage, the device can directly drive indicator LEDs and small relay coils in most designs. The built-in 60 mA short-circuit current limit provides protection against wiring faults.
The Vertiv 11205 is a chopper-stabilized Hall-effect latch that I'd recommend looking at closely for any magnetic position-sensing application where temperature range is the hard constraint. The -40°C to 150°C operating window is the spec that distinguishes it — most commercial-grade Hall latches top out at 85°C or 125°C, and the 11205's 175°C junction ceiling gives you real thermal headroom when ambient plus self-heating are both working against you.
Technical Highlights:
- Chopper Stabilization at 800 kHz: Internal offset cancellation means the 35 G / 25 G operate and release thresholds stay consistent across the full -40°C to 150°C range — you won't need to re-characterize the switching behavior at temperature extremes.
- 2 mA Quiescent Supply Current: At 2 mA draw on a 2.8–5.5 V rail, total quiescent power is under 11 mW worst-case — manageable in battery-operated sensor nodes and compatible with low-quiescent LDO regulators common in IoT designs.
- 60 mA Short-Circuit Current Limit: The output self-limits at 60 mA during a fault, which protects both the IC and the driving logic without requiring a series resistor in most applications — one fewer BOM line item.
Deployment Considerations:
- With package thermal resistance values of 228°C/W (LH) and 165°C/W (UA), verify your thermal budget before running the output at continuous 30 mA in high-ambient environments — self-heating can push junction temperature toward the 175°C limit faster than the ambient spec alone suggests.
- The 10 G hysteresis window (35 G operate, 25 G release) assumes consistent magnet alignment; lateral magnet drift in poorly constrained mechanical assemblies can shift effective operate and release points and narrow the apparent hysteresis in the field.
This part is a solid fit for industrial door-position sensors, valve-position feedback in HVAC control boards, and motor-commutation circuits in environments where the combination of wide supply tolerance, extended temperature range, and direct output drive capability eliminates the need for additional signal-conditioning components.
