[Home]Bridges - Half, Full, Three Phase

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Bridges; Half, Full, Three Phase

For the EMC2 context, a bridge is two or more of the same circuit bridged by a connection, usually for the purpose of controlling a high power load. The h-bridge is the prototype from which the half-bridge and three-phase bridge are derived. This page should contain plans, schematics and other information that can help readers to understand and appreciate how bridges work, what they can do and provide examples of what would be appropriate for a CNC application. In higher power applications the power elements can tend to switch themselves on, be hard to turn off, and/or input timing can become critical. Bridge control chips have been developed to address these problems and should also be covered here.

The most common EMC2 application of a bridge, would be a pair of h-bridges driving the pair of coils in a stepper motor in bipolar mode. Also common is an h-bridge with a PWM input signal and PWM power output driven in forward, reverse, brake, or coast through a brushed motor. Increasingly more common is a three phase bridge to drive brushless motors for axes and spindles (such as with VFD's).

(The L298 found elsewhere in this wiki should be considered part of the bridge category. Some controllers have bridges included as part of the assembly, so more insight may be found in consulting those sources.)

BLDC FAN7382 (tested 2012-03-04)
FAN7382, a monolithic half-bridge gate driver IC, can drive MOSFETs and IGBTs that operate up to +600V

BLDC IR2130 for review (not tested!!!)

The IR2130/IR2132(J)(S) is a high voltage, high speed power MOSFET and IGBT driver with three independent high and low side referenced output channels.
(Ed: I presume to be used with a gate driver, but I could be wrong -kw)

BLDC BUZ11 (tested 2012-03-04)

Three-phase half-bridge based on BUZ11's, 30A, 50V, 0.040 Ohm, N-Channel Power MOSFET

Test setup for FAN7382 and BUZ11 board


PMSM Inverter for review (not tested!!!)

FSAM10SH60A IGBT inverter bridge based, 600V-10A 3-phase
FSAM10SH60A Application ratings: Power : 0.5 kW / 100~253 Vac - Switching frequency : Typical 15kHz (PWM Control) - 100% load current : 3.3A (Irms) - 150% load current : 5.0A (Irms) for 1 minute

DC Motor with SI9978

Based on Vishay SI9978 h-bridge driver, with RS485 interface for encoder signals, for brushed DC motors
Board works: see picture near bottom of
The board is located behind the lathe chuck.

small DC Motor with SI9978 (for review, untested)


(Draft 2011/02/13 Kirk Wallace)
(edited 2012-03-04 Joachim Franek)

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Last edited March 4, 2012 1:57 am by Jjf (diff)
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