HiLetgo ACS758 ACS758LCB-050B-PFF-T 50A Linear Current Sensor ACS758LCB Current Module 120 kHz Bandwidth 3-5.5V

Some of the other reviews are saying that the through hole solder connections are too small but I just solder directly to the pins of the current sensor and it works well

quick serice

Can be safely attached when dealing with higher current demands. Solder points sized appropriately.

The holes are stupidly small! This is a nice chip from Allegro, but #1 issue: op-amp choice of this board is wrong. A 40mV per amp, a 50 amp peak (35A RMS if AC volts), the output at Vcc of 5v will be Vcc/2 + 2 = 4.5 volts. The 2272C op amp has a Vcc-1.5v or 5v - 1.5v = 3.5 volts, so the buffered output will clip the output. The unbuffered output ou1 should look good. (I didn't test this). The op amp should be a rail to rail *input* model, not just rail-rail output! #2 issue the chip is output limited If using it at 3.3v supply. The idle voltage of Vcc/2 = 1.65 v so with 40mV per amp sensitivity, the output range limits the current range to 1.65/0.04 = 41.25 volts (29 amps RMS with sinusoid AC). So, if you need 50A peak / 35A RMS, then skip the buffered output, power at 5v and use your own op amp on the unbuffered output IF you need to bias the output for a 3.3 volt A/D input. If you need 3.3v yet are OK being limited at 28 amps, use the unbuffered output without the opamp. That said, the unbuffered output might be fine, just don't load it with a low impedance.

The holes are too small for anything bigger than 14 ga wire so keep them short.

The biggest advantage of this module is its printed circuit board. It's easy to prototype with and it's cheap. Kudos to Mr James Murdock for catching the #1 issue with the buffer 2272C op amp -- it doesn't support rail-to-rail input. It may not be a problem though if AC current sensing is not required and DC current flows from IP- to IP+. Since the quiescent output is Vcc/2 at I=0, the output will stay in the lower half of the Vcc. However, I don't see the range limitation James described in his issue #2. The sensor's magnetic sensitivity is NOT 40 mV per Amp at 3.3 Vcc. It is 40 mV/A only at 5 Vcc. Its datasheet states: "Ratiometry. The device features a ratiometric output. This means that the quiescent voltage output, VIOUTQ, and the magnetic sensitivity, Sens, are proportional to the supply voltage, VCC." I just measured it. My 3.3 V supply runs a little high at 3.52 V and my Vcc/2 is 1.76 V. My measured magnetic sensitivity is 28.16 mV/A as it should be at 3.52 Vcc. Lastly, regarding the PCB holes being too small, the solid workaround is to solder your heavy gauge wire directly onto the J-leads of the sensor chip.

Very frustrating that I have #6 wires and no way to hook this. The holes are so close together - getting any lug on it is impossible. It baffles me how they think these will not be returned.