CST2020 Series
Current Sense Transformers
- Sensed current up to 40 Amps
- For use between 400 Hz to 1 MHz
- Very low primary resistance
- AEC-Q200 Grade 1 (−40°C to +125°C)
- Meets Reinforced Insulation per UL 60950-1.
- 4000 Vrms, one minute isolation (hipot) winding to winding
- RoHS-compliant. 260°C compatible. Tin-silver-copper over tin over copper over steel (pins 1 – 3); Tin-silver-copper over tin over nickel over copper (pins 4 – 5) terminations
SPECIFICATIONS
Dimensions 
Typical Circuit 
Temperature vs Current 
3D model
| Part number Click to get parts |
Turns (N) pri : sec |
Inductance1 min (mH) |
DCR max2 (Ohms) |
Freq range (kHz) |
Volt‑time product3 (Vµsec) |
Sensed current4 Iin (A) |
Terminating resistance RT5 (Ohms) |
|
|---|---|---|---|---|---|---|---|---|
| Pri | Sec | |||||||
| CST2020-070L | 1 : 70 | 3.46 | 0.00084 | 0.83 | 1.8 | 277 | 40 | 1.75 |
| CST2020-100L | 1 : 100 | 7.07 | 0.00084 | 1.23 | 1.3 | 395 | 40 | 2.5 |
| CST2020-200L | 1 : 200 | 28.28 | 0.00084 | 3.95 | 0.60 | 791 | 40 | 5.0 |
| CST2020-300L | 1 : 300 | 63.63 | 0.00084 | 7.84 | 0.40 | 1186 | 40 | 7.5 |
| 1 | Inductance measured between secondary pins at 10 kHz, 0.1 Vrms, 0 Adc. | |
| 2 | DCR at 25°C. For other operating temperatures, use this DCR at Temperature calculator. | |
| 3 | Maximum volt-time product is for the secondary, based on 2000 Gauss. | |
| 4 | Primary current of 40 A causes less than 40°C temperature rise from 25°C ambient. Higher current causes a greater temperature rise (see Temperature Rise vs Current curve). | |
| 5 | Terminating resistance (RT) value is based on 1 Volt output with 40 Amps flowing through the primary. Varying terminating resistance increases or decreases output Voltage/Ampere according to the following equation: RT (Ohms) = Vout × Nsec / Iin. |
|
| 6 | Ambient temperature range: | −40°C to +125°C |
| 7 | Maximum part temperature: | +165°C (ambient + temp rise) |
| 8 | Storage temperature range: | Component: −40°C to +165°C Tape and reel packaging: −40°C to +80°C |
| 9 | Electrical specifications at 25°C. | |
| Refer to Soldering Coilcraft Components before soldering. | ||
| PCB washing: Tested to MIL-STD-202 Method 215 plus an additional aqueous wash. More info.. | ||
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