SQ1922EEH-T1_GE3

Key Specs

Spec	Value	Condition	Source
Configuration	2 N-Channel (Dual)		Digi-Key
Current Continuous Drain ID 25 C	840mA (Tc)		Digi-Key
Drain-source Voltage (Max)	20V		Digi-Key
FET Feature	-		Digi-Key
Gate Charge Qg Max VGS	1.2nC @ 4.5V		Digi-Key
Grade	Automotive		Digi-Key
Input Capacitance Ciss Max VDS	50pF @ 10V		Digi-Key
Mounting Type	Surface Mount		Digi-Key
Operating Temperature Range	-55°C ~ 175°C (TJ)		Digi-Key
Package Case	6-TSSOP, SC-88, SOT-363		Digi-Key
Power (Max)	1.5W		Digi-Key
Qualification	AEC-Q101		Digi-Key
RDS On Max ID VGS	350mOhm @ 400mA, 4.5V		Digi-Key
Supplier Device Package	SC-70-6		Digi-Key
Technology	MOSFET (Metal Oxide)		Digi-Key
VGS Th Max ID	1.5V @ 250µA		Digi-Key

When To Use

1. Automotive 12V system switching at 1A load: The SQ1922EEH-T1_GE3 supports continuous drain current up to 840mA (typical) and pulsed current up to 3A, with a 10V drain-to-source max rating, making it suitable for low-voltage automotive auxiliary circuits. Using a higher voltage MOSFET risks shoot-through or avalanche breakdown under load transients common in automotive environments.

2. Battery-powered sensor with 5V rail and <1.2A peak current: Its low gate charge (1.2nC @ 4.5V) and typical Rds(on) of 0.35Ω at 25°C enable efficient switching at moderate current, reducing switching losses and extending battery life. A synchronous buck controller with higher gate charge would cause excessive switching losses and degrade battery runtime.

3. Industrial control signal switching at up to 1A with tight thermal constraints: The AEC-Q101 qualification and max junction temperature of 150°C allow reliable operation in harsh environments. Using a standard MOSFET without automotive qualification risks early failure due to latch-up or thermal runaway under extended high temperature cycling.

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When Not To Use

1. High current DC-DC converter >3A load: The maximum pulsed current rating of 3A and continuous current of 840mA limit this MOSFET for high current stages. Use a high-current synchronous buck with external FETs designed for higher current and improved efficiency.

2. Switching frequency above 500kHz for compact inductors: The gate charge and gate resistance limit switching speed and efficiency at frequencies over 500kHz. Use a high-frequency buck controller optimized for low gate charge and fast switching.

3. Low dropout linear regulation with <1V input-output differential: The Rds(on) and switching nature make this device unsuitable for low dropout, low noise applications. Use an LDO regulator when noise and low dropout voltage are critical.

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Application Notes

• The switching node (SW) pin must be routed with minimal loop area and a low-inductance ground return to avoid voltage spikes that can exceed the 10V drain-to-source max rating. Place the output capacitor close to the SQ1922EEH-T1_GE3 to stabilize SW node voltage.

• Noise-sensitive pins include the gate drive input and source connection; guard these with ground fills and keep gate traces short to minimize ringing and false triggering.

• The gate resistance varies from 4.5Ω to 13.7Ω max, so external gate resistors are typically unnecessary but can be added for EMI control. Avoid long gate traces which increase parasitic inductance and cause erratic switching.

• Ensure thermal vias under the package pad connect to a large copper area to maintain junction temperature below 150°C, especially at continuous currents near 840mA.

• The device is optimized for surface mount (SC-70-6) with pad diameters between 0.010 and 0.026 inches; PCB footprint must follow recommended land pattern for consistent solder joint reliability.

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Gotchas

1. [Gate threshold voltage variation under temperature]: The gate threshold varies from 0.5V (min) to 1.5V (max) and shifts with temperature. Assuming a fixed gate drive voltage of 4.5V without margin can cause incomplete turn-on at low temperatures, leading to higher Rds(on) and thermal stress. Fix: Verify gate drive voltage across the full temperature range and measure actual Rds(on) in-system.

2. [Switching node voltage overshoot]: The 10V maximum drain-to-source rating is tight for automotive transients. Layout-induced parasitic inductance on the SW node can cause voltage spikes exceeding this rating, resulting in avalanche breakdown and device failure. Fix: Minimize loop inductance, add snubbers if needed, and verify switching node waveforms with high-bandwidth probes.

3. [Gate leakage current impact on startup]: Gate leakage current can reach up to +10mA max, which is significant in low-current bias circuits. This can cause unexpected voltage drops or false triggering during power-up sequencing. Fix: Include a gate pull-down resistor and verify startup behavior under worst-case leakage conditions.

4. [ESR of output capacitor affecting stability]: Low output capacitance (typical 21pF) and insufficient ESR can cause instability or ringing during switching transitions, especially at duty cycle ~0.5. Fix: Use output capacitors with appropriate ESR and place them close to the device to damp oscillations and ensure stable operation.