# CT433-HSWF30DR TMR Current Sensor Compact Carrier 0A to 30A, 3.3V

**Type:** Product page · **SKU:** POLOLU-5317 · **Brand:** [Pololu](https://core-electronics.com.au/brands/pololu-australia)
**Page:** https://core-electronics.com.au/ct433-tmr-current-sensor-30a-compact-carrier-3-3v-unidirectional.html ([markdown](https://core-electronics.com.au/ct433-tmr-current-sensor-30a-compact-carrier-3-3v-unidirectional.html.md))

This is the compact version of a simple carrier for Allegro’s CT433-HSWF30DR TMR-based, electrically isolated current sensor that is optimized for high...

## Pricing

- **Price:** $21.45 (inc GST) — $19.50 AUD, exc GST
- **Quantity discounts:** 10+ $18.72 (exc GST) · 25+ $18.14 (exc GST)

## Availability & dispatch

- Available with a lead time — expect dispatch between Aug 28 and Aug 31.

## Description

Pololu is offering these breakout boards with support from Allegro Microsystems as an easy way to use or evaluate their CT432/CT433 tunneling magnetoresistance (TMR), electrically isolated, high-bandwidth current sensors that are optimized for high dV/dt applications; Pololu therefore recommends careful reading of the applicable [CT432 datasheet](https://core-electronics.com.au/attachments/localcontent/ct432-datasheet_1456872ac97.pdf) or [CT433 datasheet](https://core-electronics.com.au/attachments/localcontent/ct433-datasheet_148596ac61f.pdf) before using this product. The following list details some of the sensors’ key features:

- CT432/CT433 sensors use Allegro’s patented XtremeSense™ TMR (tunneling magnetoresistance) technology for high accuracy, high bandwidth, electrically isolated current measurements.
- Sensor can be inserted anywhere along the current path and be used in applications that require electrical isolation.
- 1 mO primary current path resistance in the sensor IC, and the PCB is made with 2-layer (compact versions under 50A), 4-layer (compact versions 50A and up), or 6-layer (large versions) 2-oz copper, so very little power is lost in the module.
- TMR sensing rejects common-mode fields, so the orientation of the sensor relative to uniform external magnetic fields (e.g. the Earth’s magnetic field) has less effect on the measurement.
- Optimized for high dV/dt applications, allowing the sensor to be used in switching applications.
- High-bandwidth 1 MHz analog output voltage proportional to AC or DC currents.
- Typical 300 ns response time.
- Output is not ratiometric (i.e. the zero point and sensitivity are independent of the actual supply voltage), which provides immunity from noisy supplies.
- Optional overcurrent fault output indicates when the current magnitude exceeds 110% of the maximum linear sensing range.
- Operating temperature range of -40°C to 125°C.
- Carrier boards, available in compact and large sizes, offer a variety of ways to insert it into the current path along with 0.1"-pitch (breadboard-compatible) power, ground, and output pins.

The connection points are labeled on the silkscreen, which is on the bottom side of the compact versions and on both sides of the large versions. The bottom silkscreen also shows the direction that is interpreted as positive current flow via the **+i** arrow.

The following table lists the available CT432/CT433 carrier options:

| Pololu Item # | Part Prefix | Supply Voltage (V) | Part Suffix | Current Range | Sensitivity (mV/A) | Zero Point | Size | PCB Details |
|---|---|---|---|---|---|---|---|---|
| [\#5310](https://core-electronics.com.au/ct433-hswf20mr-tmr-current-sensor-compact-carrier-20a-3-3v.html) | CT433 | 3.0 to 3.6 (3.3 nominal) | 20MR | [±20 A](https://core-electronics.com.au/ct433-hswf20mr-tmr-current-sensor-compact-carrier-20a-3-3v.html) | 50 | 1.65 V | 0.8"×1.1" | 2 layers, 2-oz copper |
| [\#5311](https://core-electronics.com.au/pololu-ct433-hswf30mr-current-sensor-30a-3-3v.html) | 30MR | [±30 A](https://core-electronics.com.au/pololu-ct433-hswf30mr-current-sensor-30a-3-3v.html) | 33.3 |
| [\#5313](https://core-electronics.com.au/pololu-ct433-hswf50mr-tmr-current-sensor-compact-carrier-50a-3-3v.html) | 50MR | [±50 A](https://core-electronics.com.au/pololu-ct433-hswf50mr-tmr-current-sensor-compact-carrier-50a-3-3v.html) | 20 |
| [\#5315](https://core-electronics.com.au/pololu-ct433-hswf70mr-tmr-current-sensor-compact-carrier-70a-3-3v.html) | 70MR | [±70 A](https://core-electronics.com.au/pololu-ct433-hswf70mr-tmr-current-sensor-compact-carrier-70a-3-3v.html) | 14.3 |
| [\#5317](https://core-electronics.com.au/ct433-tmr-current-sensor-30a-compact-carrier-3-3v-unidirectional.html) | 30DR | [0-30 A](https://core-electronics.com.au/ct433-tmr-current-sensor-30a-compact-carrier-3-3v-unidirectional.html) | 66.7 |
| [\#5318](https://core-electronics.com.au/pololu-ct433-hswf50dr-tmr-current-sensor-compact-carrier-0a-50a-3-3v.html) | 50DR | [0-50 A](https://core-electronics.com.au/pololu-ct433-hswf50dr-tmr-current-sensor-compact-carrier-0a-50a-3-3v.html) | 40 |
| [\#5319](https://core-electronics.com.au/pololu-ct433-hswf65dr-tmr-current-sensor-compact-0a-65a-3-3v.html) | 65DR | [0-65 A](https://core-electronics.com.au/pololu-ct433-hswf65dr-tmr-current-sensor-compact-0a-65a-3-3v.html) | 30.8 |
| [\#5300](https://core-electronics.com.au/pololu-ct432-hswf20mr-tmr-current-sensor-20a-5v.html) | CT432 | 4.75 to 5.5 (5 nominal) | 20MR | [±20 A](https://core-electronics.com.au/pololu-ct432-hswf20mr-tmr-current-sensor-20a-5v.html) | 100 | 2.5 V | 2 layers, 2-oz copper |
| [\#5301](https://core-electronics.com.au/pololu-ct432-hswf30mr-tmr-current-sensor-30a-5v.html) | 30MR | [±30 A](https://core-electronics.com.au/pololu-ct432-hswf30mr-tmr-current-sensor-30a-5v.html) | 66.7 |
| [\#5302](https://core-electronics.com.au/pololu-ct432-hswf50mr-tmr-current-sensor-compact-carrier-50a-5v.html) | 50MR | [±50 A](https://core-electronics.com.au/pololu-ct432-hswf50mr-tmr-current-sensor-compact-carrier-50a-5v.html) | 40 |
| [\#5303](https://core-electronics.com.au/pololu-ct432-current-sensor-compact-carrier-65a-5v.html) | 65MR | [±65 A](https://core-electronics.com.au/pololu-ct432-current-sensor-compact-carrier-65a-5v.html) | 30.8 |
| [\#5306](https://core-electronics.com.au/pololu-ct432-hswf50dr-tmr-current-sensor-compact-carrier-0a-50a-5v.html) | 50DR | [0-50 A](https://core-electronics.com.au/pololu-ct432-hswf50dr-tmr-current-sensor-compact-carrier-0a-50a-5v.html) | 80 |
| [\#5308](https://core-electronics.com.au/pololu-ct432-hswf70dr-tmr-current-sensor-compact-carrier-0a-70a-5v.html) | 70DR | [0-70 A](https://core-electronics.com.au/pololu-ct432-hswf70dr-tmr-current-sensor-compact-carrier-0a-70a-5v.html) | 57.1 |

**Details for item #5317**

This compact carrier features the CT433-HSWF30DR, which is intended for nominal 3.3 V operation and is designed for unidirectional input current from 0 A to 30 A. This version can be visually distinguished from the other versions by the part number printed on the sensor IC.

This sensor has five required connections: the input current (IP+ and IP-), logic power (VCC and GND), and the sensor output (VOUT).

The sensor requires a supply voltage of 3.0 V to 3.6 V to be connected across the VCC and GND pads, which are labeled on the bottom silkscreen. The sensor outputs an analog voltage on VOUT that has a zero point at 0.65 V and increases by 66.7 mV per amp of input current:

VOUT = 0.65 V + 0.0667 V/A · IP

The output is not ratiometric, so the zero point and sensitivity are independent of the actual supply voltage.

The optional FLT pin is normally at VCC and is pulled low when the IP current magnitude exceeds 110% of the maximum sensing range. This pin only asserts while the fault condition is present (it is **not** latched).

**Warning:** This product is intended for use below 30 V. Working with higher voltages can be extremely dangerous and should only be attempted by qualified individuals with appropriate equipment and experience.

**Dimensions**

| Size: | 0.8" × 1.1" |
|---|---|
| Weight: | 2.3 g |

**General specifications**

| Typical operating voltage: | 3.3 V |
|---|---|
| Current sense: | 66.7 mV/A |
| Minimum logic voltage: | 3.0 V |
| Maximum logic voltage: | 3.6 V |
| Supply current: | 6 mA |
| Current range: | 0A to 30A (unidirectional 30A), 3.3V |
| Current sensor: | Allegro CT433-HSWF30DR |

**Identifying markings**

| PCB dev codes: | cs07a |
|---|---|
| Other PCB markings: | 0J14949 |

**Notes:**

 1 Typical.**File downloads**

- **[Dimension diagrams of the CT432/CT433 Current Sensor Carriers](https://core-electronics.com.au/attachments/localcontent/ct43x-current-sensor-carriers-dimensions_43605901e99.pdf) (436k pdf)**
- **3D model of the CT432/CT433 Current Sensor Compact Carriers (4MB step)**
- **Drill guide for the CT432/CT433 Current Sensor Compact Carriers (20k dxf)**
    
    This DXF drawing shows the locations of all of the board’s holes.

**Recommended links**

- **[CT432 datasheet](https://core-electronics.com.au/attachments/localcontent/ct432-datasheet_1456872ac97.pdf)**
- **[CT433 datasheet](https://core-electronics.com.au/attachments/localcontent/ct433-datasheet_148596ac61f.pdf)**
- **[Allegro product page for the CT432 TMR Current Sensor](https://www.allegromicro.com/en/products/sense/current-sensor-ics/zero-to-fifty-amp-integrated-conductor-sensor-ics/ct432)**
    
    Allegro product page for the CT432, where you can find additional application notes and other resources.
- **[Allegro product page for the CT433 TMR Current Sensor](https://www.allegromicro.com/en/products/sense/current-sensor-ics/zero-to-fifty-amp-integrated-conductor-sensor-ics/ct433)**
    
    Allegro product page for the CT433, where you can find additional application notes and other resources.

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/P/O/POLOLU-5317-1.jpg)
