Enpirion® Power Datasheet EN23F0QI 15A PowerSoC Voltage Mode Synchronous Buck With Integrated Inductor Not Recommended for New Designs Description Features The EN23F0QI is a Power System on a Chip (PowerSoC) DC-DC converter. It integrates MOSFET switches, small-signal control circuits, compensation and an integrated inductor in an advanced 12x13x3mm QFN module. It offers high efficiency, excellent line and load regulation. The EN23F0QI operates over a wide input voltage range and is specifically designed to meet the precise voltage and fast transient requirements of high-performance products. The EN23F0QI features frequency synchronization to an external clock, power OK output voltage monitor, programmable soft-start along with thermal and short circuit protection. The device’s advanced circuit design, ultra high switching frequency and proprietary integrated inductor technology delivers high-quality, ultra compact, nonisolated DC-DC conversion. • • • • • • • • • • • • • The Altera Enpirion solution significantly helps in system design and productivity by offering greatly simplified board design, layout and manufacturing requirements. In addition, overall system level reliability is improved given the small number of components required with the Altera Enpirion solution. • • • • Applications • All Altera Enpirion products are RoHS compliant and lead-free manufacturing environment compatible. 0.1µF Integrated Inductor, MOSFETs, Controller Total Solution Size Estimate 308mm2 Wide Input Voltage Range: 4.5V – 14V 1% Initial Output Voltage Accuracy Master/Slave Configuration for Parallel Operation Up to 4 Devices with 48A capability Frequency Synchronization (External Clock) Output Enable Pin and Power OK Signal Programmable Soft-Start Time Under Voltage Lockout Protection (UVLO) Short Circuit Protection Thermal Shutdown Protection RoHS compliant, MSL level 3, 260oC reflow Space Constrained Applications Distributed Power Architectures Output Voltage Ripple Sensitive Applications Beat Frequency Sensitive Applications Servers, Embedded Computing Systems, LAN/SAN Adapter Cards, RAID Storage Systems, Industrial Automation, Test and Measurement, and Telecommunications Efficiency vs. Output Current 0.47µF 100 BTMP VDDB PVIN 4.75k OFF ENABLE EAIN AVINO 1µF REA 3x 47µF 1206 RA AVIN 1µF 47nF CA RCA VFB SS M/S CGND PGND PGND FQADJ AGND 90 80 EN23F0QI ON 3x 22µF 1206 VOUT BGND VOUT RCLX RB EFFICIENCY (%) PG VIN 70 60 50 VOUT = 3.3V 40 VOUT = 2.5V 30 VOUT = 1.8V 20 VOUT = 1.2V VOUT = 1.0V 10 0 0 RFS 100k Figure 1. Simplified Applications Circuit (Footprint Optimized) 07512 CONDITIONS VIN = 12.0V AVIN = 3.3V Dual Supply 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 OUTPUT CURRENT (A) Figure 2. Highest Efficiency in Smallest Solution Size June 2, 2015 Rev D EN23F0QI Ordering Information Part Number EN23F0QI EVB-EN23F0QI Package Markings EN23F0QI EN23F0QI TAMBIENT Rating (°C) -40 to +85 Package Description 92-pin (12mm x 13mm x 3mm) QFN T&R QFN Evaluation Board Packing and Marking Information: www.altera.com/support/reliability/packing/rel-packing-and-marking.html AVIN POK 71 AGND 74 ENABLE M/S 75 73 VFB 76 72 SS EAIN 78 RCLX 79 77 NC FQADJ CGND 82 81 NC(SW) 80 NC(SW) 83 NC(SW) 87 84 NC(SW) 88 NC(SW) NC(SW) 89 NC(SW) NC(SW) 90 85 NC(SW) 91 86 NC(SW) 92 Pin Assignments (Top View) NC 1 NC 2 69 S_IN NC 3 68 BGND NC 4 67 VDDB NC 5 66 BTMP NC 6 65 PG NC 7 64 AVINO KEEP OUT 70 S_OUT 8 63 PVIN 9 62 PVIN NC 10 61 PVIN NC 11 60 PVIN NC 12 59 PVIN NC 13 58 PVIN NC 14 57 PVIN NC 15 56 PVIN NC 16 55 PVIN NC 17 54 PVIN PVIN KEEP OUT NC NC 93 PGND KEEP OUT 43 44 PGND PGND PGND 46 42 PGND PGND 41 PGND 45 40 NC(SW) PGND 38 39 NC(SW) 36 37 NC VOUT NC(SW) 35 VOUT VOUT 34 PVIN 33 PVIN 47 32 48 24 31 23 NC VOUT NC VOUT PVIN 30 PVIN 49 VOUT 50 22 VOUT 21 NC 29 NC 28 PVIN VOUT 51 26 20 27 PVIN NC VOUT 52 VOUT 53 19 25 18 VOUT NC NC Figure 3: Pin Out Diagram (Top View) NOTE A: NC pins are not to be electrically connected to each other or to any external signal, ground, or voltage. All pins including NC pins must be soldered to the PCB. Failure to follow this guideline may result in part malfunction or damage. NOTE B: Shaded area highlights exposed metal below the package that is not to be mechanically or electrically connected to the PCB. Refer to Figure 16 for details. NOTE C: White ‘dot’ on top left is pin 1 indicator on top of the device package. www.altera.com/enpirion Page 2 07512 June 2, 2015 Rev D EN23F0QI Pin Description I/O Legend: PIN P=Power NAME G=Ground NC=No Connect I/O 1-24, 36, 81 NC NC 25-35 VOUT O 37-39, 83-92 NC(SW) NC 40-46 PGND G 47-63 PVIN P 64 AVINO O 65 66 PG BTMP I/O I/O 67 VDDB O 68 BGND G 69 S_IN I 70 S_OUT O 71 POK O 72 ENABLE I 73 AVIN P 74 AGND G 75 M/S I 76 VFB I/O 77 EAIN I 78 SS I/O 79 RCLX I/O 80 FQADJ I/O 82 CGND G 93 PGND G I=Input O=Output I/O=Input/Output FUNCTION NO CONNECT – These pins may be internally connected. Do not connect them to each other or to any other electrical signal. Failure to follow this guideline may result in device damage. Regulated converter output. Connect these pins to the load and place output capacitors between these pins and PGND pins 40-43. NO CONNECT – These pins are internally connected to the common switching node of the internal MOSFETs. They are not to be electrically connected to any external signal, ground, or voltage. Failure to follow this guideline may result in damage to the device. Input/Output power ground. Connect these pins to the ground electrode of the input and output filter capacitors. See VOUT and PVIN pin descriptions for more details. Input power supply. Connect to input power supply. Decouple with input capacitor to PGND pins 44-46. Internal 3.4V linear regulator output. Connect this pin to AVIN for applications where operation from a single input voltage (PVIN) is required. If AVINO is being used, place a 1µF, X5R/X7R, capacitor between AVINO and AGND as close as possible to AVINO. Place a 0.1µF, X7R, capacitor between this pin and BTMP. See pin 65 description. Internal regulated voltage used for the internal control circuitry. Place a 0.47µF, X7R, capacitor between this pin and BGND. Ground for VDDB. Do not connect BGND to any other ground. See pin 67 description. Digital Input. This pin accepts either an input clock to phase lock the internal switching frequency or a S_OUT signal from another EN23F0QI. Leave this pin floating if not used. Digital Output. PWM signal is output on this pin. Leave this pin floating if not used. Power OK is an open drain transistor (pulled up to AVIN or similar voltage) used for power system state indication. POK is logic high when VOUT is -10% of VOUT nominal. Leave this pin floating if not used. Output enable. Applying a logic high to this pin enables the output and initiates a soft-start. Applying a logic low disables the output. ENABLE logic cannot be higher than AVIN (refer to Absolute Maximum Ratings). Do not leave floating. See Power Up/Down Sequencing section for details. 3.3V Input power supply for the controller. Place a 1µF, X7R, capacitor between AVIN and AGND. Analog ground. This is the ground return for the controller. All AGND pins need to be connected to a quiet ground. A logic level low configures the device as Master and a logic level high configures the device as a Slave. Connect to ground in standalone mode. External feedback input. The feedback loop is closed through this pin. A voltage divider at VOUT is used to set the output voltage. The mid-point of the divider is connected to VFB. A phase lead network from this pin to VOUT is also required to stabilize the loop. Optional error amplifier input. Allows for customization of the control loop for performance optimization. Leave this pin floating if not used. Soft-Start node. The soft-start capacitor is connected between this pin and AGND. The value of this capacitor determines the startup time. See Soft-Start Operation in the Functional Description section for details. Short circuit protection. Connect a 100k resistor from RCLX to ground. Adding a resistor (RFS) to this pin will adjust the switching frequency of the EN23F0QI. See Table 1 for suggested resistor values on RFS for various PVIN/VOUT combinations to maximize efficiency. Do not leave this pin floating. Connect to GND plane at all times. Not a perimeter pin. This device thermal pad must be connected to the system GND plane for heat-sinking purposes. See Layout Recommendations section. www.altera.com/enpirion Page 3 07512 June 2, 2015 Rev D EN23F0QI Absolute Maximum Ratings CAUTION: Absolute Maximum ratings are stress ratings only. Functional operation beyond the recommended operating conditions is not implied. Stress beyond the absolute maximum ratings may impair device life. Exposure to absolute maximum rated conditions for extended periods may affect device reliability. MIN MAX UNITS Pin Voltages – PVIN, VOUT, PG PARAMETER SYMBOL -0.5 15 V Pin Voltages – ENABLE, S_IN, M/S, POK -0.5 AVIN + 0.3 V Pin Voltages – AVINO, AVIN, ENABLE, S_IN, S_OUT, M/S -0.5 6.0 V Pin Voltages – VFB, SS, EAIN, RCLX, FQADJ, VDDB, BTMP -0.5 2.75 V Dual Supply PVIN Rising and Falling Slew Rate (Note 1) 0.3 25 V/ms Single Supply PVIN Rising and Falling Slew Rate (Note 1) 0.3 6 V/ms 20 A 150 °C 150 °C 260 °C 2000 V 500 V Maximum Continuous Output Current IOUT_CONT_MAX Storage Temperature Range TSTG Maximum Operating Junction Temperature -65 TJ-ABS Max Reflow Temp, 10 Sec, MSL3 JEDEC J-STD-020A ESD Rating (based on Human Body Model) ESD Rating (based on CDM) Recommended Operating Conditions SYMBOL MIN MAX UNITS Input Voltage Range PARAMETER PVIN 4.5 14.0 V AVIN: Controller Supply Voltage AVIN 2.5 5.5 V Output Voltage Range (Note 2) VOUT 0.75 3.3 V Output Current (Note 3) IOUT 0 15 A Operating Ambient Temperature TA -40 +85 °C Operating Junction Temperature TJ -40 +125 °C Thermal Characteristics SYMBOL TYP UNITS Thermal Shutdown PARAMETER TSD 160 °C Thermal Shutdown Hysteresis TSDH 35 °C Thermal Resistance: Junction to Ambient (0 LFM) (Note 3) θJA 13 °C/W Thermal Resistance: Junction to Case (0 LFM) θJC 1 °C/W Note 1: PVIN rising and falling slew rates cannot be outside of specification. For accurate power up sequencing, use a fast ENABLE logic (>3V/100µs) after both AVIN and PVIN are high. Note 2: Dropout: Maximum VOUT ≤ VIN - 2.5V Note 3: Based on 2oz. external copper layers and proper thermal design in line with EIJ/JEDEC JESD51-7 standard for high thermal conductivity boards. www.altera.com/enpirion Page 4 07512 June 2, 2015 Rev D EN23F0QI Electrical Characteristics NOTE: VIN=12V, Minimum and Maximum values are over operating ambient temperature range unless otherwise noted. Typical values are at TA = 25°C. PARAMETER MAX UNITS Operating Input Voltage SYMBOL PVIN TEST CONDITIONS MIN 4.5 TYP 14.0 V Controller Input Voltage AVIN 2.5 5.5 V AVIN Under Voltage Lock-out rising AVINUVLOR Voltage above which UVLO is not asserted 1.7 2.3 2.4 V AVIN Under Voltage Lock-out falling AVINOVLOF Voltage below which UVLO is asserted 1.7 2.1 2.3 V AVIN Pin Input Current Internal Linear Regulator Output Voltage Shut-Down Supply Current IAVIN 14 mA AVINO 3.4 V IPVINS PVIN=12V, AVIN=3.3V, ENABLE=0V 1 mA IAVINS PVIN=12V, AVIN=3.3V, ENABLE=0V 75 µA Feedback Pin Voltage VFB Feedback Pin Voltage VFB Feedback Pin Input Leakage Current IFB VOUT Rise Time tRISE Feedback Node Voltage at: PVIN = 12V, ILOAD = 0, TA = 25°C Feedback Node Voltage at: 4.5V ≤ PVIN ≤ 14V 0A ≤ ILOAD ≤ 15A, TA = -40 to 85°C VFB Pin Input Leakage Current (Note 4) CSS = 47nF (Note 4, Note 5 and Note 6) Soft Start Capacitor Range CSS_RANGE Note 4 Continuous Output Current IOUT_CONT Subject to thermal derating 0.594 0.60 0.606 V 0.588 0.60 0.612 V 5 nA -5 1.96 2.8 3.64 ms 10 47 68 nF 0 15 A ENABLE Logic High VENABLE_HIGH 4.5V ≤ VIN ≤ 14V; 1.25 AVIN V ENABLE Logic Low VENABLE_LOW 4.5V ≤ VIN ≤ 14V; 0 0.95 V ENABLE Lockout Time TENLOCKOUT fsw = 1MHz (Note 4) ENABLE Pin Input Current Switching Frequency IENABLE FSW AVIN = 5.5V ENABLE = 1.8V; ENABLE = 3.3V; ENABLE = 5.5V; 5 11 23 RFS =3.01kΩ 1.0 External SYNC Clock Frequency Lock Range FPLL_LOCK Range of SYNC clock frequency (See Table 1) S_IN Threshold – Low VS_IN_LO S_IN Clock Logic Low Level (Note 4) S_IN Threshold – High VS_IN_HI S_IN Clock Logic High Level (Note 4) S_OUT Threshold – Low VS_OUT_LO S_OUT Clock Logic Low Level (Note 4) S_OUT Threshold – High VS_OUT_HI S_OUT Clock Logic High Level (Note 4) POKLT Percentage of Nominal Output Voltage for POK to be Low POK Lower Threshold 8 0.8 1.8 1.8 90 ms 8 18 32 µA MHz 1.8 MHz 0.8 V 2.5 V 0.8 V 2.5 V % www.altera.com/enpirion Page 5 07512 June 2, 2015 Rev D EN23F0QI PARAMETER SYMBOL POK Output Low Voltage VPOKL POK Output Hi Voltage VPOKH POK pin VOH leakage current IPOKL TEST CONDITIONS MAX UNITS With 4mA Current Sink into POK 0.4 V PVIN range: 4.5V ≤ PVIN ≤ 15V AVIN V 1 µA 0.8 V VT-LOW Tie Pin to GND (Master Mode) M/S Pin Logic High VT-HIGH Pull up to AVIN Through an External Resistor REXT (Slave Mode) IM/S TYP POK High (Note 4) M/S Pin Logic Low M/S Pin Input Current MIN REXT = 15kΩ; AVIN = 3.4V; AVIN = 5.5V; 1.8 V 65 175 µA Note 4: Parameter not production tested but is guaranteed by design. Note 5: Rise time calculation begins when AVIN > VUVLO and ENABLE = HIGH. Note 6: VOUT Rise Time Accuracy does not include soft-start capacitor tolerance. www.altera.com/enpirion Page 6 07512 June 2, 2015 Rev D EN23F0QI Typical Performance Curves Efficiency vs. Output Current 100 90 90 80 80 EFFICIENCY (%) EFFICIENCY (%) Efficiency vs. Output Current 100 70 60 50 VOUT = 3.3V 40 VOUT = 2.5V 30 VOUT = 1.8V 20 VOUT = 1.2V 10 VOUT = 1.0V CONDITIONS VIN = 12.0V Single Supply 70 60 50 VOUT = 3.3V 40 VOUT = 2.5V 30 VOUT = 1.8V 20 VOUT = 1.2V 0 0 0 1 2 3 0 4 5 6 7 8 9 10 11 12 13 14 15 OUTPUT CURRENT (A) MAXIMUM OUTPUT CURRENT (A) MAXIMUM OUTPUT CURRENT (A) Output Current De-rating 16 15 14 13 12 11 10 CONDITIONS VIN = 12V TJMAX = 125°C θJA = 13°C/W 13x12x3mm QFN No Air Flow 9 8 7 6 VOUT = 1.0V VOUT = 1.2V VOUT = 1.8V VOUT = 2.5V VOUT = 3.3V 5 16.0 15.0 14.0 13.0 12.0 11.0 10.0 9.0 8.0 7.0 6.0 5.0 3 4 5 6 7 8 9 10 11 12 13 14 15 OUTPUT CURRENT (A) CONDITIONS VIN = 12V TJMAX = 125°C θJA = 10.5°C/W 13x12x3mm QFN Air Flow (200fpm) VOUT = 1.0V VOUT = 1.2V VOUT = 1.8V VOUT = 2.5V VOUT = 3.3V Output Current De-rating with Heat Sink MAXIMUM OUTPUT CURRENT (A) MAXIMUM OUTPUT CURRENT (A) 2 25 30 35 40 45 50 55 60 65 70 75 80 85 AMBIENT TEMPERATURE (°C) Output Current De-rating with Air Flow (400fpm) CONDITIONS VIN = 12V TJMAX = 125°C θJA = 9°C/W 13x12x3mm QFN Air Flow (400fpm) 1 Output Current De-rating with Air Flow (200fpm) 25 30 35 40 45 50 55 60 65 70 75 80 85 AMBIENT TEMPERATURE (°C) 16.0 15.0 14.0 13.0 12.0 11.0 10.0 9.0 8.0 7.0 6.0 5.0 VOUT = 1.0V 10 CONDITIONS VIN = 12.0V AVIN = 3.3V Dual Supply VOUT = 1.0V VOUT = 1.2V VOUT = 1.8V VOUT = 2.5V VOUT = 3.3V 25 30 35 40 45 50 55 60 65 70 75 80 85 AMBIENT TEMPERATURE (°C) 16.0 15.0 14.0 13.0 12.0 11.0 10.0 9.0 8.0 7.0 6.0 5.0 CONDITIONS VIN = 12V TJMAX = 125°C θJA = 12°C/W 13x12x3mm QFN No Air Flow Heat Sink - Wakefield Thermal Solutions P/N 651-B VOUT = 1.0V VOUT = 1.2V VOUT = 1.8V VOUT = 2.5V VOUT = 3.3V 25 30 35 40 45 50 55 60 65 70 75 80 85 AMBIENT TEMPERATURE (°C) www.altera.com/enpirion Page 7 07512 June 2, 2015 Rev D EN23F0QI Typical Performance Curves 16.0 15.0 14.0 13.0 12.0 11.0 10.0 9.0 8.0 7.0 6.0 5.0 CONDITIONS VIN = 12V TJMAX = 125°C θJA = 9.5°C/W 13x12x3mm QFN Air Flow (200fpm) Heat Sink - Wakefield Thermal Solutions P/N 651-B Output Current De-rating w/ Heat Sink and Air Flow (400fpm) MAXIMUM OUTPUT CURRENT (A) MAXIMUM OUTPUT CURRENT (A) Output Current De-rating w/ Heat Sink and Air Flow (200fpm) VOUT = 1.0V VOUT = 1.2V VOUT = 1.8V VOUT = 2.5V VOUT = 3.3V 16.0 15.0 14.0 13.0 12.0 11.0 10.0 9.0 8.0 7.0 6.0 5.0 25 30 35 40 45 50 55 60 65 70 75 80 85 AMBIENT TEMPERATURE (°C) CONDITIONS VIN = 12V TJMAX = 125°C θJA = 8°C/W 13x12x3mm QFN Air Flow (400fpm) Heat Sink - Wakefield Thermal Solutions P/N 651-B VOUT = 1.8V VOUT = 2.5V VOUT = 3.3V Output Voltage vs. Output Current Max VOUT at 15A vs. Temperature 1.005 OUTPUT VOLTAGE (V) MAXIMUM OUTPUT VOLTAGE (V) VOUT = 1.2V 25 30 35 40 45 50 55 60 65 70 75 80 85 AMBIENT TEMPERATURE (°C) 3.50 3.00 2.50 2.00 CONDITIONS VIN = 12V LOAD = 15A No Air Flow No Heat Sink 1.50 1.00 1.004 VIN = 8V 1.003 VIN = 10V 1.002 VIN = 12V 1.001 1.000 0.999 0.998 0.997 CONDITIONS CONDITIONS VOUT_NOM VIN ==5.0V 1.0V 0.996 0.50 0.995 40 45 50 55 60 65 70 AMBIENT TEMPERATURE (°C) 75 80 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 OUTPUT CURRENT (A) Output Voltage vs. Output Current Output Voltage vs. Output Current 1.205 1.805 1.204 VIN = 8V 1.203 VIN = 10V 1.202 VIN = 12V OUTPUT VOLTAGE (V) OUTPUT VOLTAGE (V) VOUT = 1.0V 1.201 1.200 1.199 1.198 1.197 1.196 1.804 VIN = 8V 1.803 VIN = 10V 1.802 VIN = 12V 1.801 1.800 1.799 1.798 1.797 CONDITIONS CONDITIONS VOUT_NOM VIN ==5.0V 1.2V 1.796 1.195 CONDITIONS VOUT_NOM = 1.8V Note: Air flow or heat sink may be required for higher currents. See derating curves. 1.795 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 OUTPUT CURRENT (A) 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 OUTPUT CURRENT (A) www.altera.com/enpirion Page 8 07512 June 2, 2015 Rev D EN23F0QI Typical Performance Curves Output Voltage vs. Output Current Output Voltage vs. Temperature 1.204 2.504 VIN = 8V 2.503 VIN = 10V 2.502 VIN = 12V OUTPUT VOLTAGE (V) OUTPUT VOLTAGE (V) 2.505 2.501 2.500 2.499 2.498 CONDITIONS VOUT_NOM = 2.5V Note: Air flow or heat sink may be required for higher currents. See derating curves. 2.497 2.496 CONDITIONS VIN = 8V VOUT_NOM = 1.2V 1.203 1.202 1.201 1.200 LOAD = 0A 1.199 LOAD = 4A 1.198 LOAD = 8A 1.197 LOAD = 12A 1.196 2.495 -40 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 OUTPUT CURRENT (A) Output Voltage vs. Temperature 1.204 1.202 OUTPUT VOLTAGE (V) CONDITIONS VIN = 10V VOUT_NOM = 1.2V 1.203 1.201 1.200 LOAD = 0A 1.199 LOAD = 4A 1.198 CONDITIONS VIN = 12V VOUT_NOM = 1.2V 1.203 1.202 1.201 1.200 LOAD = 0A 1.199 LOAD = 4A 1.198 LOAD = 8A 1.197 LOAD = 8A 1.197 LOAD = 12A 1.196 LOAD = 12A 1.196 -40 -15 10 35 60 AMBIENT TEMPERATURE ( C) 85 -40 1.202 1.201 1.200 LOAD = 0A 1.199 LOAD = 4A 1.198 LOAD = 8A 1.197 LOAD = 12A 1.196 -40 -15 10 35 60 AMBIENT TEMPERATURE ( C) 85 INDIVIDUAL OUTPUT CURRENT (A) CONDITIONS VIN = 14V VOUT_NOM = 1.2V 1.203 -15 10 35 60 AMBIENT TEMPERATURE ( C) 85 Parallel Current Share Breakdown Output Voltage vs. Temperature 1.204 OUTPUT VOLTAGE (V) 85 Output Voltage vs. Temperature 1.204 OUTPUT VOLTAGE (V) -15 10 35 60 AMBIENT TEMPERATURE ( C) 20 17.5 MASTER 15 SLAVE 12.5 IDEAL 10 7.5 CONDITIONS EN23F0QI VIN = 12V VOUT = 1.2V 5 2.5 0 0 5 10 15 20 TOTAL OUTPUT CURRENT (A) 25 www.altera.com/enpirion Page 9 07512 June 2, 2015 Rev D EN23F0QI Typical Performance Characteristics Enable Startup/Shutdown Waveform (0A) Enable Startup/Shutdown Waveform (5A) ENABLE ENABLE VOUT VOUT POK POK LOAD LOAD CONDITIONS VIN = 12V, VOUT = 3.3V, Load = 0A, Css = 47nF CIN = 3x22µF(1206), COUT = 100µF(1206) + 3x47µF(1206) CONDITIONS VIN = 12V, VOUT = 3.3V, Load = 5A, Css = 47nF CIN = 3x22µF(1206), COUT = 100µF(1206) + 3x47µF(1206) Enable Startup/Shutdown Waveform (10A) Enable Startup/Shutdown Waveform (15A) ENABLE ENABLE VOUT VOUT POK POK LOAD LOAD CONDITIONS VIN = 12V, VOUT = 3.3V, Load = 10A, Css = 47nF CIN = 3x22µF(1206), COUT = 100µF(1206) + 3x47µF(1206) CONDITIONS VIN = 12V, VOUT = 3.3V, Load = 15A, Css = 47nF CIN = 3x22µF(1206), COUT = 100µF(1206) + 3x47µF(1206) Power Up Waveform (0A) Power Up Waveform (15A) PVIN PVIN VOUT VOUT POK POK LOAD LOAD CONDITIONS VIN = 12V, VOUT = 3.3V, Load = 15A, Css = 47nF, CIN = 3x22µF(1206), COUT = 100µF(1206) + 3x47µF(1206) CONDITIONS VIN = 12V, VOUT = 3.3V, Load = 0A, Css = 47nF, CIN = 3x22µF(1206), COUT = 100µF(1206) + 3x47µF(1206) www.altera.com/enpirion Page 10 07512 June 2, 2015 Rev D EN23F0QI Typical Performance Characteristics Output Ripple at 20MHz Bandwidth VOUT = 1V (AC Coupled) Output Ripple at 20MHz Bandwidth VOUT = 1V (AC Coupled) LOAD = 0A VOUT = 1.8V (AC Coupled) VOUT = 1.8V (AC Coupled) VOUT = 3.3V (AC Coupled) VOUT = 3.3V (AC Coupled) 20mV / DIV 20mV / DIV CONDITIONS VIN = 12V, CIN = 3x22µF (1206), COUT = 3x47µF + 100µF (1206) CONDITIONS VIN = 12V, CIN = 3x22µF (1206), COUT = 3x47µF + 100µF (1206) Output Ripple at 500MHz Bandwidth Output Ripple at 500MHz Bandwidth VOUT = 1V (AC Coupled) VOUT = 1V (AC Coupled) LOAD = 0A LOAD = 2A VOUT = 1.8V (AC Coupled) VOUT = 1.8V (AC Coupled) VOUT = 3.3V (AC Coupled) VOUT = 3.3V (AC Coupled) 20mV / DIV 20mV / DIV CONDITIONS VIN = 12V, CIN = 3x22µF (1206), COUT = 3x47µF + 100µF (1206) CONDITIONS VIN = 12V, CIN = 3x22µF (1206), COUT = 3x47µF + 100µF (1206) Output Ripple at 500MHz Bandwidth VOUT = 1V (AC Coupled) LOAD = 10A Output Ripple at 500MHz Bandwidth VOUT = 1V (AC Coupled) LOAD = 6A VOUT = 1.8V (AC Coupled) LOAD = 10A VOUT = 1.8V (AC Coupled) VOUT = 3.3V (AC Coupled) VOUT = 3.3V (AC Coupled) 20mV / DIV 20mV / DIV CONDITIONS VIN = 12V, CIN = 3x22µF (1206), COUT = 3x47µF + 100µF (1206) CONDITIONS VIN = 12V, CIN = 3x22µF (1206), COUT = 3x47µF + 100µF (1206) www.altera.com/enpirion Page 11 07512 June 2, 2015 Rev D EN23F0QI Typical Performance Characteristics Load Transient from 0 to 5A (VOUT =3.3V) Load Transient from 0 to 10A (VOUT =3.3V) VOUT (AC Coupled) VOUT (AC Coupled) LOAD CONDITIONS VIN = 12V, VOUT = 3.3V CIN = 3 x 22µF (1206) COUT = 3 x 47µF (1206) + 100µF (1206) Using Best Performance Configuration LOAD Load Transient from 0 to 5A (VOUT =1V) Load Transient from 0 to 15A (VOUT =3.3V) VOUT (AC Coupled) LOAD VOUT (AC Coupled) CONDITIONS VIN = 12V, VOUT = 3.3V CIN = 3 x 22µF (1206) COUT = 3 x 47µF (1206) + 100µF (1206) Using Best Performance Configuration LOAD Load Transient from 0 to 10A (VOUT =1V) CONDITIONS VIN = 12V, VOUT = 1.0V CIN = 3 x 22µF (1206) COUT = 3 x 47µF (1206) + 100µF (1206) Using Best Performance Configuration Load Transient from 0 to 15A (VOUT =1V) VOUT (AC Coupled) LOAD CONDITIONS VIN = 12V, VOUT = 3.3V CIN = 3 x 22µF (1206) COUT = 3 x 47µF (1206) + 100µF (1206) Using Best Performance Configuration VOUT (AC Coupled) CONDITIONS VIN = 12V, VOUT = 1.0V CIN = 3 x 22µF (1206) COUT = 3 x 47µF (1206) + 100µF (1206) Using Best Performance Configuration LOAD CONDITIONS VIN = 12V, VOUT = 1.0V CIN = 3 x 22µF (1206) COUT = 3 x 47µF (1206) + 100µF (1206) Using Best Performance Configuration www.altera.com/enpirion Page 12 07512 June 2, 2015 Rev D EN23F0QI Functional Block Diagram M/S S_OUT S_IN UVLO Digital I/O BTMP PVIN PG Linear Regulator To PLL AVINO Thermal Limit Short Circuit Protection NC(SW) Gate Drive VOUT 5k BGND (-) PWM Comp (+) PGND PLL/Sawtooth Generator FADJ VDDB Compensation Networkr EAIN Compensation Network (-) Error Amp (+) VFB Power Good Logic ENABLE POK 300k R SS Soft Start Voltage Reference Generator Band Gap Reference EN23F0QI AVIN AGND Figure 4: Functional Block Diagram Functional Description small size input and output capacitors, as well as a wide loop bandwidth within a small foot print. Synchronous Buck Converter The EN23F0QI is a highly integrated synchronous, buck converter with integrated controller, power MOSFET switches and integrated inductor. The nominal input voltage (PVIN) range is 4.5V to 14V and can support up to 15A of continuous output current. The output voltage is programmed using an external resistor divider network. The control loop utilizes a Type IV Voltage-Mode compensation network and maximizes on a low-noise PWM topology. Much of the compensation circuitry is internal to the device. However, a phase lead capacitor is required along with the output voltage feedback resistor divider to complete the Type IV compensation network. The high switching frequency of the EN23F0QI enables the use of Protection Features: The power supply has the following protection features: • Short Circuit Protection • Thermal Shutdown with Hysteresis • Under-Voltage Lockout Protection Additional Features: • • • Switching Frequency Synchronization Programmable Soft-Start Power OK Output Monitoring www.altera.com/enpirion Page 13 07512 June 2, 2015 Rev D EN23F0QI Power Up Sequence The EN23F0QI is designed to be powered by either a single input supply (PVIN) or two separate supplies: one for PVIN and the other for AVIN. The EN23F0QI is not “hot pluggable.” Refer to the PVIN Slew Rate specification on page 4. Single Input Supply Application (PVIN): then to ground can be used to enable and disable the device at a programmed PVIN voltage level. The lower resistor (2.26k) can be adjusted to set startup and shutdown at a specific PVIN voltage level. In this operating mode the minimum PVIN is 6.8V due to the ENABLE threshold. See ENABLE and DISABLE thresholds in the Electrical Characteristics table. Dual Input Supply Application (PVIN and AVIN): 0.1µF PG VIN 0.47µF BTMP VDDB PVIN 3x 22µF 1206 EAIN ENABLE 2.26k AVINO 1µF 1µF 47nF REA 3x 47µF 1206 RA CA VFB RFS 3x 22µF 1206 OFF ENABLE REA 1µF 47nF RB M/S PVIN slew rate limitations as per datasheet PVIN – Recommended to be ramped down after the Vout softshutdown occurs VOUT RB 100k In this application, place a 1µF, X5R/X7R, capacitor between AVIN and AGND as close as possible to AVIN. Refer to Figure 7 for a recommended schematic for a dual input supply application. For dual input supply applications, the sequencing of the two input supplies, PVIN and AVIN, is very important. There are two common acceptable turnon sequences for the device. AVIN can always come up before PVIN. If PVIN comes up before AVIN, then ENABLE must be toggled last, after AVIN is asserted. Do not turn off AVIN before PVIN and ENABLE during shutdown. Doing so will disable the internal controller while there may still be energy in the system. The device will not softshutdown properly and damage may occur. See diagram below for a recommended startup and shutdown sequencing. 12V PVIN 3.3V Delay from ENABLE rising edge to soft start begin ~ 1ms RCLX Figure 7: Dual Input Supply Schematic 12V 0V CA PGND FQADJ AGND 100k The EN23F0QI has an internal linear regulator that converts PVIN to 3.4V. The output of the linear regulator is provided on the AVINO pin once the device is enabled. AVINO should be connected to AVIN on the EN23F0QI. In this application, the following external components are required: Place a 1µF, X5R/X7R capacitor between AVINO and AGND as close as possible to AVINO. Place a 1µF, X5R/X7R capacitor between AVIN and AGND as close as possible to AVIN. In addition, place a resistor (RVB) between VDDB and AVIN, as shown in Figure 5. Altera recommends RVB=4.75kΩ. In this application, ENABLE cannot be asserted before PVIN. See diagram below for a recommended startup and shutdown sequencing. ENABLE RA RCA CGND PGND Figure 5: Single Input Supply Schematic 0V 3x 47µF 1206 VFB SS RFS PVIN EAIN AVIN M/S RCLX VOUT BGND VOUT AVINO VAVIN PGND FQADJ AGND BTMP VDDB EN23F0QI ON RCA CGND PGND 0.47µF PVIN AVIN SS PG VIN EN23F0QI 10k 4.75k 0.1µF VOUT BGND VOUT 0V PVIN slew rate limitations as per datasheet PVIN powered down before AVIN 3.3V Delay from ENABLE falling edge to soft shutdown begin ~ 1.5ms Soft Start Time ≈ 2ms w/Css=47nF AVIN AVIN powered up before PVIN 0V 3.3V Soft Shutdown Time ≈ 1.3ms w/Css=47nF ENABLE Figure 6: Single Supply Startup/Shutdown Sequence If no external enable signal is used, a resister divider (see Figure 5) from PVIN to ENABLE and 0V Delay from ENABLE rising edge to soft start begin ~ 1ms VOUT Delay from ENABLE falling edge to soft shutdown begin ~ 1.5ms Soft Start Time ≈ 2ms w/Css=47nF PVIN/AVIN – Recommended to be ramped down after the Vout softshutdown occurs Soft Shutdown Time ≈ 1.3ms w/Css=47nF Figure 8: Dual Supply Startup/Shutdown Sequencing www.altera.com/enpirion Page 14 07512 June 2, 2015 Rev D EN23F0QI Enable Operation Pre-Bias Precaution The EN23F0QI is not designed to be turned on into a pre-biased output voltage. Be sure the output capacitors are not charged or the output of the EN23F0QI is not pre-biased when the EN23F0QI is first enabled. Frequency Synchronization The switching frequency of the EN23F0QI can be phase-locked to an external clock source to move unwanted beat frequencies out of band. The internal switching clock of the EN23F0QI can be phase locked to a clock signal applied to the S_IN pin. An activity detector recognizes the presence of an external clock signal and automatically phaselocks the internal oscillator to this external clock. Phase-lock will occur as long as the input clock frequency is in the range of 0.8MHz to 1.8MHz. The external clock frequency must be within ±10% of the nominal switching frequency set by the RFS resistor. It is recommended to use a synchronized clock frequency close to the typical frequency recommendations in Table 1. A 3.01kΩ resistor from FQADJ to ground is recommended for clock frequencies within ±10% of 1MHz. When no clock is present, the device reverts to the free running frequency of the internal oscillator set by the RFS resistor. The efficiency performance of the EN23F0QI for various PVIN/VOUT combinations can be optimized by adjusting the switching frequency. Table 1 shows recommended RFS values for various PVIN/VOUT combinations in order to optimize performance of the EN23F0QI. Rfs vs. SW Frequency 1.800 SWITCHING FREQUENCY (MHz) The ENABLE pin provides a means to enable normal operation or to shut down the device. A logic high will enable the converter into normal operation. When the ENABLE pin is asserted (high) the device will undergo a normal soft-start. A logic low will disable the converter. A logic low will power down the device in a controlled manner and the device is subsequently shut down. The ENABLE signal has to be low for at least the ENABLE Lockout Time (8ms) in order for the device to be reenabled. To ensure accurate startup sequencing the ENABLE/DISABLE signal should be faster than 1V/100µs. A slower ENABLE/DISABLE signal may result in a delayed startup and shutdown response. Do not leave ENABLE floating. 1.600 1.400 1.200 1.000 CONDITIONS VIN = 6V to 12V VOUT = 0.8V to 3.3V 0.800 0.600 0 2 4 6 8 10 12 14 16 18 20 22 RFS RESISTOR VALUE (kΩ) Figure 9. RFS versus Switching Frequency The efficiency performance of the EN23F0QI for various VOUTs can be optimized by adjusting the switching frequency. Table 1 shows recommended RFS values for various VOUTs in order to optimize performance of the EN23F0QI. PVIN 12V 5V VOUT 3.3V 2.5V 1.8V 1.5V 1.2V <1.0V 2.5V 1.8V 1.5V 1.2V <1.0V RFS 22k 10k 4.87k 3.01k 1.65k 1.3k 22.1k 10k 6.65k 4.87k 3.01k Typical fsw 1.42 MHz 1.3 MHz 1.15 MHz 1.0 MHz 0.95 MHz 0.8 MHz 1.4 MHz 1.3 MHz 1.25 MHz 1.15 MHz 1.0 MHz Table 1: Recommended RFS Values Soft-Start Operation Soft start is a means to ramp the output voltage gradually upon start-up. The output voltage rise time is controlled by the choice of soft-start capacitor, which is placed between the SS pin and the AGND pin. During start-up of the converter, the reference voltage to the error amplifier is linearly increased to its final level by an internal current source of approximately 10µA. The soft-start time is measured from when VIN > VUVLOR and ENABLE pin voltage crosses its logic high threshold to when VOUT reaches its programmed value. The total softstart time can be calculated by: Soft Start Time (ms): T SS ≈ Css [nF] x 0.06 www.altera.com/enpirion Page 15 07512 June 2, 2015 Rev D EN23F0QI POK Operation The POK signal is an open drain signal (requires a pull up resistor to AVIN or similar voltage) from the converter indicating the output voltage is within the specified range. Typically, a 100kΩ or lower resistance is used as the pull-up resistor. The POK signal will be logic high (AVIN) when the output voltage is above 90% of the programmed voltage level. If the output voltage is below this point, the POK signal will be a logic low. The POK signal can be used to sequence down-stream converters by tying to their enable pins. Short Circuit Protection The short circuit protection feature will protect the device if the output is shorted to ground. Short circuit protection is achieved by sensing the current flowing through a sense PFET. When the sensed current exceeds the threshold for more than 32 cycles, both power FETs are turned off for the rest of the switching cycle. If the short circuit condition is removed, the device will reactivate soft-start and resume PWM operation. In the event the short circuit trips consistently in normal operation, the device enters a hiccup mode. While in hiccup mode, the device is disabled for a short while and restarted with a normal soft-start. The hiccup time is approximately 32ms. This cycle can continue indefinitely as long as the short circuit condition persists. Use a resistor value of 100k from the RCLX pin to ground to enable this feature. Thermal Overload Protection Thermal shutdown circuit will disable device operation when the junction temperature exceeds approximately 160ºC. After a thermal shutdown event, when the junction temperature drops by approx 35ºC, the converter will re-start with a normal soft-start. AVIN Under-Voltage Lock-Out (UVLO) Internal circuits ensure that the converter will not start switching until the input voltage is above the specified minimum voltage. Hysteresis, input deglitch and output leading edge blanking ensures Master / Slave (Parallel) Operation: Up to four EN23F0QI devices may be connected in a Master/Slave configuration to handle larger load currents. The maximum output current for each parallel device will need to be de-rated by 20 percent so that no devices will over current due to current mis-match. The Master device’s switching clock may be phase-locked to an external clock source via the S_IN pin or left open and use its default switching frequency. The device is placed in Master mode by pulling the M/S pin low or in Slave mode by pulling M/S pin high. Note that the M/S pin is also pulled low for standalone mode. In Master mode, the internal PWM signal is output on the S_OUT pin. This PWM signal from the Master is fed to the Slave device at its S_IN input. The Slave device acts like an extension of the power FETs in the Master. The inductor in the Slave prevents crow-bar currents from Master to Slave due to timing delays. Parallel operation in dual supply mode is shown in Figure 11. Single supply mode operation may also be implemented, but be sure not to tie AVINs together. Note that only critical components are shown. The red text and red lines indicate the important parallel operation connections and care should be taken in layout to ensure low impedance between those paths. The parallel current matching is illustrated in Figure 10 Parallel Current Share Breakdown INDIVIDUAL OUTPUT CURRENT (A) Typical soft-start time is approximately 2.8ms with SS capacitor value of 47nF. high noise immunity and prevents false UVLO triggers. 20 17.5 MASTER 15 SLAVE 12.5 IDEAL 10 7.5 CONDITIONS EN23F0QI VIN = 12V VOUT = 1.2V 5 2.5 0 0 5 10 15 20 TOTAL OUTPUT CURRENT (A) 25 Figure 10. Parallel Current Matching www.altera.com/enpirion Page 16 07512 June 2, 2015 Rev D EN23F0QI Note 2: The Master and Slave VOUTs should be connected with very low iµpedance as shown by the double red line connections in parallel. Note 1: The Master and Slave VINs should be connected with very low iµpedance as shown by the double red line connections in parallel. VIN PVIN ENA 3x 22µF 1206 AVIN AVIN 3x 47µF 1206 EN23F0QI (MASTER) RA CA VFB SS 47nF VOUT VOUT R1 M/S PGND PGND S_OUT AGND RB FQADJ S_IN PVIN AVIN 3x 22µF 1206 15k VOUT ENA 3x 47µF 1206 EN23F0QI (SLAVE) AVIN VFB M/S open SS PGND PGND FQADJ AGND 47nF Slave #1 Note 4: Up to 3 Slaves µay be used in parallel with the Master Note 3: The Master and Slave PGNDs should be connected with very low iµpedance as shown by the double red line connections in parallel. Figure 11. Parallel Operation Illustration www.altera.com/enpirion Page 17 07512 June 2, 2015 Rev D EN23F0QI Application Information Output Voltage Programming and Loop Compensation The EN23F0QI uses a Type IV Voltage Mode compensation network. Type IV Voltage Mode control is a proprietary Altera Enpirion control scheme that maximizes control loop bandwidth to deliver excellent load transient responses and maintain output regulation with pin point accuracy. For ease of use, most of this network has been customized and is integrated within the device package. The EN23F0QI output voltage is programmed using a simple resistor divider network (RA and RB). The feedback voltage at VFB is nominally 0.6V. RA is predetermined based on Table 4 and RB can be calculated based on Figure 12. The values recommended for COUT, CA, RCA and REA make up the external compensation of the EN23F0QI. It will vary with each PVIN and VOUT combination to optimize on performance. The EN23F0QI solution can be optimized for either smallest size or highest performance. Please see Table 4 for a list of recommended RA, CA, RCA, REA and COUT values for each solution. Since VFB is a sensitive node, do not touch the VFB node while the device is in operation as doing so may introduce parasitic capacitance into the control loop that causes the device to behave abnormally and damage may occur. VOUT COUT RA CA REA RCA VFB VFB = 0.6V PGND RB = EN23F0QI Recommended Input Capacitors Description MFG P/N 22µF, 16V, X5R, 10%, 1206 Murata GRM31CR61C226ME15 22µF, 16V, X5R, 20%, 1206 Taiyo Yuden EMK316ABJ226ML- T 22µF, 25V, X5R, 10%, 1210 Murata GRM32ER61E226KE15L 22µF, 25V, X5R, 20%, 1210 Taiyo Yuden TMK325BJ226MM- T Table 2: Recommended Input Capacitors Output Capacitor Selection As seen from Table 4, the EN23F0QI has been optimized for use with one 100µF/1206 plus three 47µF/1206 output capacitors for best performance. For smallest solution size, various combinations of output capacitance may be used. See Table 4 for details. Low ESR ceramic capacitors are required with X5R or X7R rated dielectric formulation. Y5V or equivalent dielectric formulations must not be used as these lose too much capacitance with frequency, temperature and bias voltage. Table 3 contains a list of recommended output capacitors. Output ripple voltage is determined by the aggregate output capacitor impedance. Capacitor impedance, denoted as Z, is comprised of capacitive reactance, effective series resistance, ESR, and effective series inductance, ESL reactance. Placing output capacitors in parallel reduces the impedance and will hence result in lower ripple voltage. VOUT EAIN capacitors are needed in parallel with the larger, capacitors in order to provide high frequency decoupling. Table 2 contains a list of recommended input capacitors. VFB x RA 1 VOUT - VFB Figure 12: VOUT Resistor Divider & Compensation Components. See Table 4 for details. Input Capacitor Selection The EN23F0QI requires three 22µF/1206 input capacitor. Low-cost, low-ESR ceramic capacitors should be used as input capacitors for this converter. The dielectric must be X5R or X7R rated. Y5V or equivalent dielectric formulations must not be used as these lose too much capacitance with frequency, temperature and bias voltage. In some applications, lower value Z Total = 1 1 1 + + ... + Z1 Z 2 Zn Recommended Output Capacitors Description 47µF, 6.3V, X5R, 20%, 1206 47µF, 10V, X5R, 20%, 1206 22µF, 10V, X5R, 20%, 0805 100µF, 6.3V, X5R, 20%, 1206 MFG P/N Murata GRM31CR60J476ME19L Taiyo Yuden LMK316BJ476ML- T Taiyo Yuden LMK212BJ226MG- T Murata GRM31CR60J107ME39L Taiyo Yuden JMK316BJ107ML-T Table 3: Recommended Output Capacitors www.altera.com/enpirion Page 18 07512 June 2, 2015 Rev D EN23F0QI Best Performance Smallest Solution Size CIN = 3 x 22µF/1206 CIN = 3 x 22µF/1206 VOUT ≤ 1.8V, COUT = 22µF/0805 + 2x47µF/0805 3.3V > VOUT> 1.8V, COUT = 3x47µF/1206 RA = 100 kΩ COUT = 3x47µF (1206) + 100µF(1206) RA = 200 kΩ PVIN VOUT (V) (V) 14V 12V 10V 8V 6.6V 5V CA RCA REA (pF) (kΩ) (kΩ) Ripple (mV) Deviation (mV) 1.0V 1.2V 1.5V 1.8V 2.5V 3.3V 1.0V 1.2V 1.5V 1.8V 2.5V 3.3V 1.0V 1.2V 1.5V 1.8V 2.5V 3.3V 1.0V 1.2V 1.5V 1.8V 2.5V 3.3V 1.0V 1.2V 1.5V 1.8V 2.5V 3.3V 1.0V 1.2V 27 27 27 15 15 15 27 27 27 15 15 15 27 27 27 15 15 15 27 27 27 15 15 15 27 27 27 15 15 15 27 27 15 15 15 15 15 15 15 15 15 15 15 15 5 5 5 15 15 15 5 5 5 5 5 5 1 1 1 5 5 5 1 1 200 200 200 86 86 86 200 200 200 86 86 86 86 86 86 86 86 86 86 86 86 86 86 86 86 86 86 86 86 86 86 86 25.6 24 26.4 28.4 31.6 37.3 21.6 22.7 25.2 25.8 30 30.8 18.8 20.4 22 23.6 26.5 28.9 17.2 18.7 20.1 20.9 23.6 22.8 13.8 15.2 16.4 19.6 20.4 21.1 12.4 13.4 40 42 60 70 86 96 42 48 70 72 82 110 46 54 60 78 92 132 64 64 70 100 120 156 74 76 88 116 148 204 92 100 1.5V 1.8V 2.5V 27 15 15 1 5 5 86 86 86 14.3 15.4 15.5 120 160 204 PVIN (V) 14V 12V 10V 8V 6.6V 5V VOUT (V) CA RCA (pF) (kΩ) REA (kΩ) Ripple (mV) Deviation (mV) 1.0V 1.2V 1.5V 1.8V 2.5V 3.3V 1.0V 1.2V 1.5V 1.8V 2.5V 3.3V 1.0V 1.2V 1.5V 1.8V 2.5V 3.3V 1.0V 1.2V 1.5V 1.8V 2.5V 3.3V 1.0V 1.2V 1.5V 1.8V 2.5V 3.3V 1.0V 1.2V 12 12 12 12 15 10 22 22 18 18 22 15 56 47 39 33 33 22 200 200 150 82 68 39 200 200 200 150 100 56 200 200 36 36 36 36 27 27 27 27 27 27 27 27 20 20 20 20 20 20 10 10 10 10 10 10 10 10 10 10 10 10 10 10 Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open Open 15 18 22 25 32 46 15 18 21 24 30 43 15 17 20 22 29 41 14 16 19 20 27 36 13 15 17 19 24 32 12 13 78 93 104 130 162 200 84 97 118 130 172 213 85 100 120 140 177 230 83 90 107 138 178 239 99 105 118 138 183 250 123 132 1.5V 1.8V 2.5V 200 200 100 10 10 10 Open Open Open 16 17 20 145 156 216 3.3V 15 5 86 12.9 300 3.3V 100 10 Open 21 253 Table 4: RA, CA, RCA and REA Values for Various PVIN/VOUT Combinations: Best Performance vs. Smallest Solution Size. Use the equations in Figure 12 to calculate RB. Output ripple is measured at no load and nominal deviation is for a 15A load transient step. For compensation values of output voltage in between the specified output voltages, choose compensation values of the lower output voltage setting. www.altera.com/enpirion Page 19 07512 June 2, 2015 Rev D EN23F0QI Thermal Considerations Thermal considerations are important power supply design facts that cannot be avoided in the real world. Whenever there are power losses in a system, the heat that is generated by the power dissipation needs to be accounted for. The Altera Enpirion PowerSoC helps alleviate some of those concerns. η = POUT / PIN = 80% = 0.8 The Altera Enpirion EN23F0QI DC-DC converter is packaged in a 13x12x3mm 92-pin QFN package. The QFN package is constructed with copper lead frames that have an exposed thermal pad. The exposed thermal pad on the package should be soldered directly on to a copper ground pad on the printed circuit board (PCB) to act as a heat sink. The recommended maximum junction temperature for continuous operation is 125°C. Continuous operation above 125°C may reduce long-term reliability. The device has a thermal overload protection circuit designed to turn off the device at an approximate junction temperature value of 160°C. PD = PIN – POUT The following example and calculations illustrate the thermal performance of the EN23F0QI. Example: VIN = 12V VOUT = 1.2V PIN ≈ 18W / 0.8 ≈ 22.5W The power dissipation (PD ) is the power loss in the system and can be calculated by subtracting the output power from the input power. ≈ 22.5W – 18W ≈ 4.5W With the power dissipation known, the temperature rise in the device may be estimated based on the theta JA value (θJA). The θJA parameter estimates how much the temperature will rise in the device for every watt of power dissipation. The EN23F0QI has a θJA value of 13 ºC/W without airflow. Determine the change in temperature (ΔT) based on PD and θJA. ΔT = PD x θJA ΔT ≈ 4.5W x 13°C/W = 58.5°C ≈ 59°C The junction temperature (T J ) of the device is approximately the ambient temperature (T A) plus the change in temperature. We assume the initial ambient temperature to be 25°C. T J = T A + ΔT T J ≈ 25°C + 59°C ≈ 84°C IOUT = 15A First calculate the output power. POUT = 1.2V x 15A = 18W Next, determine the input power based on the efficiency (η) shown in Figure 13. Efficiency vs. Output Current 100 80 70 60 50 VOUT = 3.3V 40 VOUT = 2.5V 30 VOUT = 1.8V 20 VOUT = 1.2V VOUT = 1.0V 10 The maximum operating junction temperature (T JMAX) of the device is 125°C, so the device can operate at a higher ambient temperature. The maximum ambient temperature (T AMAX) allowed can be calculated. T AMAX = T JMAX – PD x θJA ≈ 125°C – 59°C ≈ 66°C The maximum ambient temperature the device can reach is 66°C given the input and output conditions. Note that the efficiency will be slightly lower at higher temperatures and this calculation is an estimate. Check De-rating Curves for guaranteed maximum output current over temperature. 90 EFFICIENCY (%) PIN = POUT / η CONDITIONS VIN = 12.0V AVIN = 3.3V Dual Supply 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 OUTPUT CURRENT (A) Figure 13: Efficiency vs. Output Current For VIN = 12V, VOUT = 1.2V at 15A, η ≈ 80% www.altera.com/enpirion Page 20 07512 June 2, 2015 Rev D EN23F0QI Engineering Schematic A single through-hole test point connects the AGND pin to the GND plane. An optional resistor (Rea) may be connected from VFB to EAIN for control loop optimization Css 0402 47n X7R Rclx 0402 100k Rf s 22k M/S must be tied to the ground plane for stand alone operation Cav in 1u 0402 X7R EAIN Rfs values chosen for 12Vin/3.3Vout Enable can also be driven with an external logic signal depending on the application. POK AGND 71 POK 72 73 AVIN ENABLE 75 76 74 AGND M/S VFB 77 78 SS EAIN 80 79 RCLX FQADJ 81 NC81 83 82 PVIN { PVIN 70 69 68 67 66 65 Cin1 Cout2 Cin2 Rv b 4.75k 0402 Cpg 0.1u 0402 X5R 64 63 Cav ino 1u 0402 X7R 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 PVIN = 12V } Cin1--Cin3: 22u 1206 25V X5R Cin3 Output capacitors & compensation network optimized for 12Vin to 3.3Vout. See datasheet for other Vin/Vout cases. Cb 0.47u 0402 X5R PVIN Cout1 Cout3 Choose RPOK so that the max sink current is not exceeded. 46 45 44 43 42 41 40 34 33 32 31 PGND NC23 PGND PVIN PGND PVIN NC22 PGND NC21 PGND PVIN PGND PVIN NC20 PGND NC19 NC(SW)39 PVIN VOUT NC18 NC24 Cout1-Cout3: 47u 1206 6.3V X5R CGND NC(SW)83 85 84 NC(SW)84 NC(SW)85 PVIN VOUT PVIN NC17 VOUT NC16 25 0402 86 PVIN VOUT PVIN NC15 VOUT 24 NC14 VOUT 23 PVIN 30 22 PVIN NC13 29 21 0201 87 U1 EN23F0 VOUT 20 0402 NC(SW)86 PVIN VOUT 19 0402 88 PVIN NC11 28 18 Rb 22.1k NC(SW)87 NC10 27 17 27k NC(SW)88 PVIN VOUT 16 Rca 89 NC9 VOUT 15 Ra 100k 90 PVIN 26 14 Ca 15p 91 AVINO NC8 NC12 13 VOUT NC7 39 12 PG NC(SW)38 11 NC6 NC(SW)37 10 BTMP 38 9 VDDB NC5 NC36 8 NC4 37 7 S_IN 36 6 S_OUT BGND VOUT 5 0402 100k NC3 35 4 NC(SW)89 NC2 3 NC(SW)90 NC1 2 NC(SW)91 1 NC(SW)92 92 RPOK Connect input and output caps to GND plane through mulitple vias. (See the Gerber files.) Figure 14: Engineering Schematic for Smallest Solution Size www.altera.com/enpirion Page 21 07512 June 2, 2015 Rev D EN23F0QI Layout Recommendation Figure 15: Top Layer Layout with Critical Components (Top View). See Figure 14 for corresponding schematic. This layout only shows the critical components and top layer traces for minimum footprint in single-supply mode. Alternate circuit configurations & other low-power pins need to be connected and routed according to customer application. Please see the Gerber files at www.altera.com/enpirion for details on all layers. Recommendation 1: Input and output filter capacitors should be placed on the same side of the PCB, and as close to the EN23F0QI package as possible. They should be connected to the device with very short and wide traces. Do not use thermal reliefs or spokes when connecting the capacitor pads to the respective nodes. The +V and GND traces between the capacitors and the EN23F0QI should be as close to each other as possible so that the gap between the two nodes is minimized, even under the capacitors. Recommendation 2: The PGND connections for the input and output capacitors on layer 1 need to have a slit between them in order to provide some separation between input and output current loops. Recommendation 3: The system ground plane should be the first layer immediately below the surface layer. This ground plane should be continuous and un-interrupted below the converter and the input/output capacitors. Recommendation 4: The thermal pad underneath the component must be connected to the system ground plane through as many vias as possible. The drill diameter of the vias should be 0.33mm, and the vias must have at least 1 oz. copper plating on the inside wall, making the finished hole size around 0.200.26mm. Do not use thermal reliefs or spokes to connect the vias to the ground plane. This connection provides the path for heat dissipation from the converter. Recommendation 5: Multiple small vias (the same size as the thermal vias discussed in recommendation 4) should be used to connect ground terminal of the input capacitor and output capacitors to the system ground plane. It is preferred to put these vias along the edge of the GND copper closest to the +V copper. These vias connect the input/output filter capacitors to the GND plane, and help reduce parasitic inductances in the input and output current loops. If vias cannot be placed under the capacitors, then place them on both sides of the slit in the top layer PGND copper. Recommendation 6: AVIN is the power supply for the small-signal control circuits. AVINO powers AVIN in single supply mode. AVIN and AVINO should have a decoupling capacitor close to each of their pins. Refer to Figure 15. Recommendation 7: The layer 1 metal under the device must not be more than shown in Figure 15. Refer to the section regarding Exposed Metal on Bottom of Package. As with any switch-mode DC/DC converter, try not to run sensitive signal or control lines underneath the converter package on other layers. Recommendation 8: The VOUT sense point should be just after the last output filter capacitor. Keep the sense trace short in order to avoid noise coupling into the node. Contact Altera MySupport for any remote sensing applications. Recommendation 9: Keep RA, CA, RB, and RCA close to the VFB pin (Refer to Figure 15). The VFB pin is a high-impedance, sensitive node. Keep the trace to this pin as short as possible. Whenever possible, connect RB directly to the AGND instead of going through the GND plane. Recommendation 10: Follow all the layout recommendations as close as possible to optimize performance. Altera provides schematic and layout reviews for all customer designs. Contact Altera for detailed support MySupport (www.altera.com/mysupport). www.altera.com/enpirion Page 22 07512 June 2, 2015 Rev D EN23F0QI Design Considerations for Lead-Frame Based Modules Exposed Metal on Bottom of Package Lead-frames offer many advantages in thermal performance, in reduced electrical lead resistance, and in overall foot print. However, they do require some special considerations. In the assembly process lead frame construction requires that, for mechanical support, some of the lead-frame cantilevers be exposed at the point where wire-bond or internal passives are attached. This results in several small pads being exposed on the bottom of the package, as shown in Figure 16. Only the thermal pad and the perimeter pads are to be mechanically or electrically connected to the PC board. The PCB top layer under the EN23F0QI should be clear of any metal (copper pours, traces, or vias) except for the thermal pad. The “shaded-out” area in Figure 16 represents the area that should be clear of any metal on the top layer of the PCB. Any layer 1 metal under the shaded-out area runs the risk of undesirable shorted connections even if it is covered by soldermask. The solder stencil aperture should be smaller than the PCB ground pad. This will prevent excess solder from causing bridging between adjacent pins or other exposed metal under the package. Please consult the EN23F0 Package Soldering Guidelines for more details and recommendations. Figure 16: Lead-Frame exposed metal (Bottom View) Shaded area highlights exposed metal that is not to be mechanically or electrically connected to the PCB. www.altera.com/enpirion Page 23 07512 June 2, 2015 Rev D EN23F0QI Recommended PCB Footprint Figure 17: EN23F0QI PCB Footprint (Top View) The solder stencil aperture for the thermal pad (shown in blue) is based on Altera’s manufacturing recommendations. www.altera.com/enpirion Page 24 07512 June 2, 2015 Rev D EN23F0QI Package and Mechanical Figure 18: EN23F0QI Package Dimensions (Bottom View) Packing and Marking Information: www.altera.com/support/reliability/packing/rel-packing-and-marking.html Contact Information Altera Corporation 101 Innovation Drive San Jose, CA 95134 Phone: 408-544-7000 www.altera.com © 2013 Altera Corporation—Confidential. All rights reserved. ALTERA, ARRIA, CYCLONE, ENPIRION, HARDCOPY, MAX, MEGACORE, NIOS, QUARTUS and STRATIX words and logos are trademarks of Altera Corporation and registered in the U.S. Patent and Trademark Office and in other countries. All other words and logos identified as trademarks or service marks are the property of their respective holders as described at www.altera.com/common/legal.html. Altera warrants performance of its semiconductor products to current specifications in accordance with Altera's standard warranty, but reserves the right to make changes to any products and services at any time without notice. Altera assumes no responsibility or liability arising out of the application or use of any information, product, or service described herein except as expressly agreed to in writing by Altera. Altera customers are advised to obtain the latest version of device specifications before relying on any published information and before placing orders for products or services. www.altera.com/enpirion Page 25 07512 June 2, 2015 Rev D