IXRFD631-NRF

30 A Low-Side RF MOSFET Driver IXRFD631 Features Description • High Peak Output Current • Low Output Impedance • Low Quiescent Supply Current • Low Propagation Delay • High Capacitive Load Drive Capability • Wide Operating Voltage Range • Kelvin Ground The IXRFD631 is a CMOS highspeed, high-current gate driver specifically designed to drive MOSFETs in Class D and E HF RF applications as well as other applications requiring ultrafast rise and fall times or short minimum pulse widths. The IXRFD631 is an improved version of the IXRFD630 with a Kelvin ground connection on the input side to allow use of a common mode choke to avoid problems with ground bounce. It can source and sink 30 A of peak current while producing voltage rise and fall times of less than 4 ns and minimum pulse widths of 8 ns. The input of the driver is compatible with +5 V or CMOS and is fully immune to latch up over the entire operating range. Designed with small internal delays, cross conduction or current shoot-through is virtually eliminated. The features and wide safety margin in operating voltage and power make the IXRFD631 unmatched in performance and value. Applications • RF MOSFET Driver • Class D and E RF Generators • Multi-MHz Switch Mode Supplies • Pulse Transformer Driver • Pulse Laser Diode Driver • Pulse Generator The surface mount IXRFD631 is packaged in a lowinductance RF package incorporating advanced layout techniques to minimize stray lead inductances for optimum switching performance. Fig. 1- Block Diagram and Truth Table IN OUT 0 0 1 1 1 IXRFD631 30 A Low-Side RF MOSFET Driver Absolute Maximum Ratings Parameter Value Parameter Value Supply Voltage VCC 30 V Maximum Junction Temperature 150° C Input Voltage Level VIN -5 V to VCC + 0.3 V Operating Temperature Range -40° C to 85° C All Other Pins -0.3 V to VCC +0.3 V Thermal Impedance (Junction to Case) RӨJC 0.25° C/W Power Dissipation TA( AMBIENT) ≤ 25°C TC (CASE) ≤ 25°C 2W 100 W Storage Temperature -40° C to 150° C Soldering Lead Temperature (10 seconds maximum) 300° C Note: Operating the device outside of the “Absolute Maximum Ratings” may cause permanent damage. Typical values indicate conditions for which the device is intended to be functional but do not guarantee specific performance limits. The guaranteed specifications apply only for the test conditions listed. Exposure to absolute maximum conditions for extended periods may impact device reliability. Electrical Characteristics Unless otherwise noted, TA = 25° C, 8V < VCC < 30V. All voltage measurements with respect to GND. IXRFD631 configured as described in Test Conditions. Test Conditions Min Typ 3.5 3 Symbol Parameter VIH High input voltage VCC = 15V for typical value VIL Low input voltage VCC = 15V for typical value VHYS Input hysteresis VIN Input voltage range IIN VOH VOL Input current High output voltage Low output voltage 0V≤ VIN ≤ VCC ROH High output resistance VCC = 15V IOUT = 100mA 0.25 Ω ROL Low output resistance VCC = 15V IOUT = 100mA 0.17 Ω IPEAK Peak output current VCC = 15V 28 A IDC Continuous output current 2.5 A tR Rise time VCC=15V CL=1nF CL=2nF 4 5 ns ns tF Fall time VCC =15V CL=1nF CL=2nF 4 5.5 ns ns tONDLY ON propagation delay VCC=15V CL=2nF 24 ns tOFFDLY OFF propagation delay VCC=15V CL=2nF 22 ns PW min Minimum pulse width FWHM VCC=15V CL=1nF 8 ns VCC Power supply voltage ICC Power supply current Recommended VCC = 15V VIN = 0V VCC = 15V VIN = 3.5V VCC = 15V VIN = VCC 2.8 Max V 0.8 V V VCC + 0.3 V 10 µA V V 0.23 -5 -10 VCC - 0.025 0.025 8 15 0 1 0 Units 18 1 3 5 V mA mA mA CAUTION: These devices are sensitive to electrostatic discharge; follow proper ESD procedures when handling and assembling. 2 IXRFD631 30 A Low-Side RF MOSFET Driver Fig, 2 Fig, 3 Output Resistance vs. Supply Voltage 3.5 0.4 VIH 3 Input Threshold (V) 0.35 Output Resistance (Ω) Input Threshold vs. Supply Voltage 0.3 ROH 0.25 0.2 ROL 0.15 0.1 VIL 2.5 2 1.5 1 0.5 0.05 0 0 0 5 10 15 20 25 30 35 0 5 Supply Voltage (V) Fig, 4 7 Fig, 5 20 25 30 Rise Time vs Supply Voltage 8 CLOAD = 4nF 7 CLOAD = 3nF CLOAD = 4nF 6 5 Rise Time (ns) Fall Time (ns) 15 Supply Voltage (V) Fall Time vs Supply Voltage 6 CLOAD = 2nF 4 CLOAD = 1nF 3 C LOAD = 0nF 2 CLOAD = 3nF 5 CLOAD = 2nF 4 CLOAD = 1nF 3 2 1 CLOAD = 0nF 1 0 0 5 10 15 5 20 10 Supply Voltage (V) Fig, 6 Propagation Delay vs. Supply Voltage 40 7 35 6 30 ON Delay (TDON) 25 OFF Delay (TDOFF) 20 15 20 Supply Voltage (V) Fig, 7 Supply Current (mA) Propagation Delay (ns) 10 15 10 Quiescent Current vs Supply Voltage 5 Input High 4 3 2 Input Low 1 5 0 0 5 10 15 Supply Voltage (V) 20 5 10 15 20 25 Supply Voltage (V) 3 IXRFD631 30 A Low-Side RF MOSFET Driver Supply Current vs. Frequency Vcc = 8V 3.5 3 Supply Current (A) Supply Current vs. Frequency Vcc = 12V Fig, 9 2.5 C = 4nF 6 C = 3nF 5 C = 2nF 2 C = 1nF 1.5 1 Supply Current (A) Fig, 8 C = 1nF 2 0 0 20 30 C = 2nF 3 1 10 C = 3nF 4 0.5 0 C = 4nF 0 40 10 Frequency (MHz) Fig, 10 8 20 30 40 Frequency (MHz) Supply Current vs. Frequency Vcc = 15V Supply Current vs Load Capacitance Vcc = 8V Fig, 11 2.5 C = 4nF C = 3nF 6 5 C = 2nF 4 C = 1nF 3 2 2 Supply Current (A) Supply Current (A) 7 25 MHz 1.5 20 MHz 1 10 MHz 0.5 1 0 5 MHz 0 0 10 20 30 40 0 1 Frequency (MHz) Supply Current vs Load Capacitance Vcc = 12V Fig, 13 3.5 4 3 3.5 Supply Current (A) Supply Current (A) Fig, 12 2.5 25 MHz 2 20 MHz 1.5 10 MHz 1 2 3 4 Load Capacitance (nF) 5 MHz 0.5 Supply Current vs Load Capacitance Vcc = 15V 3 25 MHz 2.5 20 MHz 2 10 MHz 1.5 1 5 MHz 0.5 0 0 0 1 2 Load Capacitance (nF) 3 4 0 1 2 3 4 Load Capacitance (nF) 4 30 A Low-Side RF MOSFET Driver Fig, 14 Fig, 15 Peak Sink Current vs. Supply Voltage Peak Source Current vs. Supply Voltage 50 45 -10 Peak Source Current (A) Peak Sink Current (A) 0 -20 -30 -40 -50 -60 40 35 30 25 20 15 10 5 -70 0 0 10 20 30 40 0 5 10 Supply Voltage (V) Fig, 16 Peak Source Current vs. Temperature Vcc = 15V Fig, 17 20 25 30 Peak Sink Current vs. Temperature Vcc = 15V -20 -22 Source Current (A) 30 Source Current (A) 15 Supply Voltage (V) 35 25 20 15 10 -24 -26 -28 -30 -32 -34 -36 5 -38 0 -40 -50 0 50 -50 100 0 Fig, 18 1.5 50 100 Temperature (°C) Temperature (°C) Fig, 19 Rise Time Normalized vs. Temperature Vcc = 15V 1.5 Fall Time Normalized vs. Temperature Vcc = 15V 1.4 1.4 1.3 1.3 1.2 1.2 Fall Time Rise Time IXRFD631 1.1 1 0.9 1.1 1 0.9 0.8 0.8 0.7 0.7 0.6 0.6 0.5 0.5 -50 0 50 Temperature (°C) 100 -50 0 50 100 Temperature (°C) 5 30 A Low-Side RF MOSFET Driver IXRFD631 Fig. 20 Pin Description Symbol Function Vcc Supply Voltage IN Input IN GND Input Ground OUT Output Driver Output. For application purposes, this lead is connected directly to the Gate of a MOSFET Power Ground System ground leads. Internally connected to all circuitry, these leads provide ground reference for the entire device and should be connected to a low noise analog ground plane for optimum performance. GND Description Positive power supply voltage input. These leads provide power to the entire device. Input signal-TTL or CMOS compatible. Input Kelvin ground connection Fig. 21 Test Circuit Diagram Note: If required, a common mode choke can be added to further stabilize the input. Usually a few nano-henries on a small core will be sufficient to eliminate threshold variations due to ground bounce. Fig. 22 Timing Diagram 6 30 A Low-Side RF MOSFET Driver IXRFD631 Fig. 23 Package Diagram Top View End View Bottom View Side View DCB – Direct Copper Bond under Nickel plate on a Aluminum Nitride substrate and is electrically isolated from any pin. 7 30 A Low-Side RF MOSFET Driver Applications Information Introduction Circuits capable of very high switching speeds and high frequency operation require close attention to several important issues. Key elements include circuit loop inductance, Vcc bypassing, and grounding. Circuit Loop Inductance The Vcc to Vcc Ground current path defines the loop that generates the inductive term. This loop must be kept as short as possible. The output lead must be no further than 0.375 inches (9.5 mm) from the gate of the MOSFET. Furthermore, the output ground leads must provide a balanced symmetric coplanar ground return for optimum operation. Vcc Bypassing In order to turn a MOSFET on properly, the IXRFD631 must be able to draw up to 30 A of current from the Vcc power supply in 2-6 ns (depending upon the input capacitance of the MOSFET being driven). Good performance requires very low impedance between the driver and the power supply. The most common method of achieving this low impedance is to bypass the power supply at the driver with a capacitance value much larger than the load capacitance. Usually, this is achieved by placing two or three different types of bypassing capacitors, with complementary impedance curves, very close to the driver itself. (These capacitors should be carefully selected for low inductance, low resistance, and high pulse current service.) Care should be taken to keep the lengths of the leads between these bypass capacitors and the IXRFD631 to an absolute minimum. IXRFD631 Output Lead Inductance Of equal importance to supply bypassing and grounding are issues related to the output lead inductance. Every effort should be made to keep the leads between the driver and its load as short and wide as possible, and treated as coplanar transmission lines. In configurations where the optimum configuration of circuit layout and bypassing cannot be used, a series resistance of a few ohms in the gate lead may be necessary to dampen ringing. Heat Sinking For high power operation, the bottom side metalized substrate should be placed in compression against an appropriate heat sink. The substrate is metalized for improved heat dissipation, and is not electrically connected to the device or to ground. See the technical note “DE-Series MOSFET and IC Mounting Instructions” on the IXYS Colorado website at www.ixyscolorado.com for detailed mounting instructions. The bypassing should be comprised of several values of MLC (Multi-Layer Ceramic) capacitors symmetrically placed on either side of the IC. Recommended values are 0.01 uF and 0.47 uF for bypass and at least two 4.7 uF tantalums for bulk storage. Grounding In order for the design to turn the load off properly, the IXRFD631 must be able to drain 30 A of current into an adequate grounding system. There are two paths for returning current that need to be considered: Path one is between the IXRFD631 and its load, and path two is between the IXRFD631 and its power supply. Both of these paths should be as low in resistance and inductance as possible, and thus as short as practical. IXYS Colorado 1609 Oakridge Dr. Suite 100 Fort Collins, CO Phone: 970-493-1901 Fax: 970-232-3025 Dec. 2012 8 Disclaimer Notice - Information furnished is believed to be accurate and reliable. However, users should independently evaluate the suitability of and test each product selected for their own applications. Littelfuse products are not designed for, and may not be used in, all applications. Read complete Disclaimer Notice at www.littelfuse.com/disclaimer-electronics.