85V Half Bridge MOSFET Drivers with 5.5V to 16V Gate Drive MIC4604 Evaluation Board General Description Getting Started The MIC4604 is an 85V Half Bridge MOSFET driver. The 1. Connect V supply between the VIN and GND IN MIC4604 features fast 39ns propagation delay times and terminals and V supply between the VDD and DD 20ns driver rise/fall times for a 1nF capacitive load. The GND terminals. low-side and high-side gate drivers are independently Connect a supply between the VIN terminal (J2) and controlled. The MIC4604 has TTL input thresholds. It the GND terminal (J3), paying careful attention to includes a high-voltage internal diode that helps charge polarity and supply range (V 85V). Do not apply IN the high-side gate drive bootstrap capacitor. power until Step 5. The MIC4604YM Evaluation Board comes with the Connect a supply between the VDD terminal (J1) and MIC4604YM SOIC package, while the MIC4604YMT the GND terminal (J3), paying careful attention to Evaluation Board comes with the MIC4604YMT TDFN polarity and supply range (5.5V V < 16V). Do not DD package. apply power until Step 5. Datasheets and support documentation are available on 2. Connect the TTL-compatible HI and LI inputs. Micrels web site at: www.micrel.com. Connect the HI input (JP2) and LI input (JP3) to a pulse generator or the output of a PWM control IC. Requirements Ensure that they are non-overlapping signals and are At a minimum, the evaluation board requires a 5.5V to 16V TTL compatible logic-levels. power supply to power the VDD terminal (J1) of the MIC4604 and another supply (up to 85V) may be used to 3. Monitor inputs and outputs. power the MOSFETs connected to the VIN terminal (J2). A Monitor the inputs HI (JP2) and LI (JP3) and outputs pulse generator or the output of a PWM control IC may be HO (JP1) and LO (JP4) with an oscilloscope. connected to the HI and LI terminals. 4. Connect motor across HS and GND or connect HS Precautions to GND. There is no reverse input protection on this board. When The simplest way to observe the MIC4604 operation is connecting the input sources, make sure that the correct to connect a motor across the HS terminal (J8) and polarity is observed. GND (J9). Alternatively the HS terminal (J8) can be Under extreme load conditions and with a high supply shorted to GND (J9) with the V supply turned OFF. IN voltage (>48V) connected to the VIN terminal (J2), input DC and AC parameters can be easily measured in this transients can be quite large if long test leads are used. In configuration. such cases a 100F, 100V electrolytic capacitor is needed 5. Turn on supplies and HI/LI inputs. across the VIN terminals to prevent overvoltage damage to the IC. This can be removed if a clean supply voltage on Turn on the V power supply followed by the V IN DD VIN is always guaranteed. power supply. Turn on the HI and LI inputs. Because there is no non-overlap protection, always ensure Ordering Information that the HI/LI inputs are connected to non-overlapping clock signals as shown in Figures 1, 2, 3, and 4. If both HI Part Number Description and LI are ON at the same time, then HO and LO will be 85V Half Bridge Driver Evaluation high at the same time and turn ON both the MOSFETs, MIC4604YM EV Board with MIC4604YM device. thus shorting the VIN supply to GND. 85V Half Bridge Driver Evaluation MIC4604YMT EV Board with MIC4604YMT device. Micrel Inc. 2180 Fortune Drive San Jose, CA 95131 USA tel +1 (408) 944-0800 fax + 1 (408) 474-1000 Micrel, Inc. MIC4604 Evaluation Board Evaluation Board Performance Figure 1. 4kHz Motor Operation Figure 2. 4kHz Motor Operation Showing LI, HI, LO, and HO Signals Showing LI, HI, HS, and HO Signals Figure 3. 4kHz Motor Operation Figure 4. HS tied to GND Showing LI, HI, HS, and LO Signals Showing LI, HI, LO, and HO Signals Revision 1.0 September 11, 2013 2