EV Charging

EV (Electric Vehicle) Chargers. On a background: electric cars on electric car charging station

EMI resilience is a crucial requirement for power related applications such as EV charging – whether the charging station is in a public space with multiple ports or is a single standalone unit typically used in residential locations.

SiTime MEMS timing products offer system design engineers unique features to reduce radiated EMI in EV chargers with programmable drive strength and spread spectrum capability.

Download Application Brief

SiTime MEMS Timing Benefits

Less power and smaller size

Small form factor

Low power consumption

Ideal features for EV

Extended temp range

EMI reduction

Built to last

No quartz reliability issues

More resilient

Electric Vehicle Supply Equipment (EVSE)

Electric vehicle supply equipment (EVSE), commonly called charging stations or charging docks, have three to four main sub-systems depending on the type of equipment, each requiring EMI protection from other sub-systems. Filtering, shielding and improved PCB layout are a means of reducing EMI, but these techniques can be costly and consume extra space. Reducing the noise generated by the clock is a fast and less costly approach. SiTime MEMS products offer such noise reduction benefits.

Level 1 and 2 chargers (AC chargers) have subsystems for AC-DC conversion, HMI and system monitoring at a minimum.
Level 3 charger (DC chargers) have an additional sub-system for DC-DC conversion.
Battery buffered charging stations allow for the batteries in the EVSE to be charged during off peak hours helping defray the high recurring cost of using electricity during peak hours. Instead of use a DC-DC sub-system, these chargers require a battery management system (BMS) to monitor the health of the batteries and will benefit from SiTime SiT8021 or SiT9025 oscillators.

Level 3 EV Charging Station Block Diagram

SiTime Timing Solutions Advantages

SiTime devices offer the following advantages over quartz crystals, which are particularly important for industrial applications.

EMI reduction thru either spread spectrum or programmable drive strength.
Higher reliability and resilience.
No activity dip or cold start issues.
Wide operating temperature range (up to -40°C to 125°C).

MEMS Timing for EV Charging

Devices	Key Features	Key Values
Single-ended Oscillator SiT8021 1 to 26 MHz	-40°C to 85°C ±20 ppm stability 1.5 x 0.8 package	High reliability Extended temperature range Small footprint
Single-ended Oscillator SiT1602 3.57 to 77.76 MHz	-40°C to 85°C ±20 ppm stability 2.0 x 1.6 package	Programmable drive strength Fast startup time of 5 ms 100% pin-to-pin replacement to quartz XO
Spread Spectrum Oscillator SiT9025 1 to 150 MHz	Up to -55°C to 125°C ±25 or ±50 ppm stability Configurable rise / fall times 2016, 2520, 3225 packages AEC-Q100 qualified	EMI reduction High reliability Programmable drive strength Extended temperature range
Spread Spectrum Oscillator SiT9005 1 to 141 MHz	±25 or ±50 ppm stability -40°C to 85°C Configurable rise / fall times 2016, 2520, 3225 packages	EMI reduction High reliability Programmable drive strength Extended temperature range
32.768 kHz Oscillator SiT1811 32.768 kHz	±20, ±50, ±100 ppm stability 1.14 to 3.63 V supply <490 nA consumption Up to -40°C to 105°C 1.2 x 1.1 mm package <115 ms startup time	Low power Small footprint Excellent stability Faster start-up time than 32.768 kHz tuning-fork crystal enables faster system start-up