DEIC515 15 Ampere Low-Side Ultrafast RF MOSFET Driver Features • Built using the advantages and compatibility of CMOS and IXYS HDMOSTM processes • Latch-Up Protected • High Peak Output Current: 15A Peak • Wide Operating Range: 8V to 30V • Rise And Fall Times of <4ns • Minimum Pulse Width Of 8ns • High Capacitive Load Drive Capability: 2nF in <4ns • Matched Rise And Fall Times • 18ns Input To Output Delay Time • Low Output Impedance • Low Quiescent Supply Current Applications • • • • • • • • Driving RF MOSFETs Class D or E Switching Amplifier Drivers Multi MHz Switch Mode Power Supplies (SMPS) Pulse Generators Acoustic Transducer Drivers Pulsed Laser Diode Drivers DC to DC Converters Pulse Transformer Driver Description The DEIC515 is a CMOS high speed high current gate driver specifically designed to drive MOSFETs in Class D, E, and HF, RF applications at up to 45MHz, as well as other applications requiring ultrafast rise and fall times or short minimum pulse widths. The DEIC515 can source and sink 15A of peak current while producing voltage rise and fall times of less than 4ns, and minimum pulse widths of 8ns. The input of the driver is fully immune to latch up over the entire operating range. Its features and wide safety margin in operating voltage and power make the DEIC515 unmatched in performance and value. The DEIC515 is packaged in DEI's low inductance RF package incorporating DEI's patented (1) RF layout techniques to minimize stray lead inductances for optimum switching performance. The DEIC515 is a surface-mount device. (1) DEI U.S. Patent #4,891,686 Figure 1 - DEIC515 Functional Diagram VCC IN IN IN GND VCC OUT DGND DEIC515 Absolute Maximum Ratings (Note 1) Parameter Value 15 Ampere Low-Side Ultrafast RF MOSFET Driver Supply Voltage VCC / VCCIN 30V (Note 2) Parameter Maximum Junction Temperature Input Voltage Level VIN -5V to VCCIN + 0.3V (Note 2) Operating Temperature Range All Other Pins -0.3V to (VCC ,VCCIN)+0.3V Power Dissipation TAMBIENT ≤ 25C Tcase ≤ 25C 2W 100W Storage Temperature -40°C to 150°C Soldering Lead Temperature (10 seconds maximum) 300°C Value 150oC -40oC to 85oC Thermal Impedance (Junction To Case) θJC 0.13oC/W Electrical Characteristics Unless otherwise noted, TA = 25° C, 8V < VCC =VCCIN < 30V. All voltage measurements with respect to DGND. DEIC515 configured as described in Test Conditions. Symbol Parameter VIH VIL VIN IIN VOH VOL ROH ROL IPEAK IDC fMAX High input voltage Low input voltage Input voltage range Input current High output voltage Low output voltage Output resistance @ Output High Output resistance @ Output Low Peak output current Continuous output current Maximum frequency tR Rise time tF Fall time tONDLY On-time propagation delay Off-time propagation delay tOFFDLY PWmin Minimum pulse width Test Conditions Typ Max VCCIN -2 0V≤ VIN ≤VCC,VCCIN VCC,VCCIN 0.025 V V V µA V V 0.8 VCC + 0.3 10 -5 -10 - .025 Units IOUT = 10mA, VCC = 15V 0.55 0.85 Ω IOUT = 10mA, VCC = 15V 0.35 0.85 Ω VCC,VCCIN = 15V 15 A 2.5 A CL=2nF VCC,VCCIN =15V CL=1nF VCC,VCCIN =15V VOH=2V to 12V CL=2nF VCC,VCCIN =15V VOH=2V to 12V CL=1nF VCC,VCCIN =15V VOH=12V to 2V CL=2nF VCC,VCCIN =15V VOH=12V to 2V 2.5 4.1 2.5 3.9 45 MHz ns ns ns ns CL=2nF Vcc=15V 17.4 18.5 ns CL=2nF Vcc=15V 14.6 16 ns FWHM CL=1nF VCC,VCCIN =15V +3V to +3V CL=1nF VCC,VCCIN =15V 6.4 8.2 Input Impeadance Z IN VCC,VCCIN Power supply voltage f = 1MHz ICC VIN = 0V VIN = VCCIN Power supply current Min 8 7960 15 0 ns ns 30 10 10 Ω V µA µA Note 1: Operating the device beyond parameters with listed “Absolute Maximum Ratings” may cause permanent damage to the device. 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 rated conditions for extended periods may affect device reliability. Note 2: VccIN / VIN must be within ±0.3V of VCC due to the upper P channel switch of the output stage. Conduction will occur when VCCIN is less than VCC resulting in a negative VGS on this P channel switch. DEIC515 15 Ampere Low-Side Ultrafast RF MOSFET Driver Lead Description - DEIC515 SYMBOL VCC VCCIN IN OUT PGND INGND FUNCTION DESCRIPTION Output section voltage supply leads. These leads provide power to the output Output Supply Voltage stage. Both VCC leads must be connected. Input section voltage supply lead. This lead provides power to the input stage. Supply Voltage This lead should not be directly connected to VCC. Input Drive signal input. Output Drive signal output. The system ground leads. Internally connected to all circuitry, these leads provide ground reference for the entire chip. These leads should be connected to a low noise Power Ground analog ground plane for optimum performance. Input Ground The input ground lead. This lead is a Kelvin connection internally connected to PGND. This lead must not be connected externally to PGND as excessive current can damage this lead. CAUTION: These devices are sensitive to electrostatic discharge; follow proper ESD procedures when handling and assembling this component. Figure 2 - DEIC515 Package Photo And Lead Diagram DEIC515 15 Ampere Low-Side Ultrafast RF MOSFET Driver Figure 3 - Characteristics Test Diagram INVCC VCC VCC IN + 10µF Input - + L1 OUT CL 10µF INGND GND Common Mode Choke Application The very high currents and high speeds inside the DEIC515 create very large transients. To avoid problems with false triggering, the input to the DEIC515 should be supplied via a common mode choke. This is a simple tri-filar winding on a small ferrite core. This prevents high speed transients from impacting the input signal by allowing it to follow the internal die potential changes without changing the state of the input. DEIC515 15 Ampere Low-Side Ultrafast RF MOSFET Driver Fig. 5 Rise Time vs. Supply Voltage Fall Times vs. Supply Voltage 20 20 15 15 Fall Time (nS) Rise Time (nS) Fig. 4 CLOAD = 7nF 10 CLOAD = 4nF CLOAD = 7nF 10 CLOAD = 4nF 5 5 CLOAD = 1nF CLOAD = 1nF 0 0 5 10 15 20 5 25 10 Fig. 6 Fig. 7 Rise \ Fall Times vs. Temperature VCC \ VCCIN \ VIN = 15V CLOAD = 1000pF 25 Rise Times vs. Load Capacitance VCC \ VCCIN \ VIN = 8V - 25V 12 5 Rise Time (nS) Rise \ Fall Time (ns) 20 14 6 tOFF 4 tON 3 10 8 6 4 2 -50 2 0 50 1 100 10 Load Capacitance (nF) Temperature (C) Fig. 8 Propagation ON Delay vs. Supply Voltage Rising VIN Input Fig. 9 Fall Tim es vs. Load Capacitance V CC \ V CCIN \ V IN = 8V - 25V 24 Propagation Delay Time (nS) 14 12 Fall Time (nS) 15 VCC \ VCCIN \ VIN (V) VCC \ VCCIN \ VIN (V) 10 8 6 4 22 20 CLOAD = 7nF 18 16 CLOAD = 4nF 14 12 CLOAD = 1nF 10 2 1 Load Capacitance (nF) 10 5 10 15 20 VCC \ VCCIN \ VIN (V) 25 30 DEIC515 15 Ampere Low-Side Ultrafast RF MOSFET Driver Fig. 11 Propagation OFF Delay vs. Supply Voltage Falling V IN Input 20 18 16 CLOAD = 7nF 14 CLOAD = 4nF 12 Propagation Delay vs. Temperature VCC \ VCCIN \ VIN = 15V CLOAD = 1000pF 17 22 Propagation Delay Time (nS) Propagation Delay Tim e (nS) Fig. 10 CLOAD = 1nF 10 16 15 tONDLY 14 13 tOFFDLY 12 11 10 5 10 15 20 25 -50 30 0 Fig. 13 VCCIN Supply Current vs. Frequency VIN \ VCCIN = VCC CLOAD = 1000pF VIN \ VCC = VCCIN CLOAD = 7000pF 0.1 V CCIN = 20V V CCIN = 20V V CCIN = 15V V CCIN = 15V V CCIN = 8V VCCIN Current (A) 1 VCCIN Current (A) VCCIN Supply Current vs. Frequency 10 10 V CCIN = 8V 0.01 1 0.1 0.01 0.001 0 10 20 30 40 0 50 5 Fig. 14 10 15 20 Fig. 15 VCC Supply Current vs. Frequency 30 VCC Supply Current vs. Frequency VIN \ VCCIN = VCC CLOAD = 7000pF VIN \ VCCIN =VCC CLOAD = 1000pF 10 10 V CC = 20V VCC Current (A) V CC = 20V V CC = 15V V CC = 8V 1 25 Frequency (MHz) Frequency (MHz) VCC Current (A) 100 Temperature (°C) V CC \ V CCIN \ V IN (V) Fig. 12 50 0.1 V CC = 15V V CC = 8V 1 0.1 0.01 0.01 0 10 20 30 Frequency (MHz) 40 50 0 5 10 15 20 Frequency (MHz) 25 30 DEIC515 15 Ampere Low-Side Ultrafast RF MOSFET Driver Fig. 17 Output Source Current vs. Supply Voltage 30 -5 25 -10 Sink Current (A) Source Current (A) Fig. 16 20 15 10 Output Sink Current vs. Supply Voltage -15 -20 -25 -30 5 5 10 15 20 25 5 30 10 15 17 -15 16 -16 Sink Current (A) Source Current (A) Fig. 19 Output Source Current vs. Temperature VCC \ VCCIN \ VIN = 15V 15 14 13 12 30 Output Sink Current vs. Tem perature V CC \ V CCIN \ V IN = 15V -17 -18 -19 -20 -21 11 10 -50 0 50 100 Fig. 20 High \ Low State Output Resistance vs. Supply Voltage 0.8 0.7 0.6 High St at e 0.5 0.4 Low St at e 0.3 5 10 15 20 V CC / V CCIN (V) -22 -50 0 50 Tem perature (C) Temperature (C) O utput Resistance (Ω) 25 V CC \ V CCIN \ V IN VCC \ VCCIN \ VIN Fig. 18 20 25 30 100 DEIC515 Application Information 15 Ampere Low-Side Ultrafast RF MOSFET Driver 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 which will generate the inductive term. This loop must be kept as short as possible. The output lead must be no further than 0.375 inches (9.5mm) 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 DEIC515 must be able to draw up to 15A of current from the Vcc power supply in 2-6ns (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, low inductance, low resistance, high-pulse-current-service capacitors.) Care should be taken to keep the lengths of the leads between these bypass capacitors and the DEIC515 to an absolute minimum. The bypassing should be comprised of several values of chip capacitors symmetrically placed on either side of the IC. Recommended values are .01uF and .47uF chips and at least two 4.7uF tantalums. Grounding In order for the design to turn the load off properly, the DEIC515 must be able to drain this 15A of current into an adequate grounding system. There are two paths for returning current that need to be considered: Path #1 is between the DEIC515 and its load, and path #2 is between the DEIC515 and its power supply. Both of these paths should be as low in resistance and inductance as possible, and thus as short as practical. The DEI515 has separate ground leads for input and power which allows the addition of a common mode choke at the input and input ground leads. The common mode choke will provide a means of preventing ground bounce from affecting the input to the driver. The selection of the common mode choke is related to the device being driven, the board layout, and the Vcc bypassing. 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 prevent 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 DEI technical note “DE-Series MOSFET and IC Mounting Instructions” on the IXYSRF website at www.ixysrf.com for detailed mounting instructions. DEIC515 15 Ampere Low-Side Ultrafast RF MOSFET Driver Fig. 21- Dimensional Drawing Bottom View