DEMO MANUAL DC2422A-A, DC2422A-B, DC2422A-C LTC7812EUH Wide VIN, Step-Up + Step-Down DC/DC Converter DESCRIPTION Demonstration circuit DC2422A is a step-up + step-down DC/DC converter featuring the LTC®7812EUH, a high performance dual output (Boost + Buck) synchronous DC/ DC switching regulator controller. This board has three different configurations: n n n DC2422A-A:Regulated VOUT to 12V DC2422A-B:Quasi regulated VOUT between 10V and 16V DC2422A-C:Dual outputs:12V (boost channel) 5V (buck channel) This circuit enables a drop-in layout where the total circuit area is only 1½" by 1". The LTC7812EUH is in a 32-lead exposed pad QFN package. The main features of the board include rail tracking (buck channel only), an internal 5V linear regulator for bias, separate RUN pins for each output and a Mode selector that allows the converter to run in CCM, pulse skip or Burst Mode® operation. Synchronization to an external clock is also possible. PERFORMANCE SUMMARY SYMBOL PARAMETER VIN VOUT1 The LTC7812 buck input is supplied from the boost output for the DC2422A-A and DC2422A-B only. With this boostthen-buck topology, the buck output maintains regulation over the entire input range. The wide input voltage range of 4V to 36V is suitable for automotive or other battery fed applications where low quiescent current is important. The DC2422A-B is designed such that VOUT is partially regulated between 10V and 16V for higher efficiency (Figure 4a), reduced power loss, and switching noise. When VIN is between 10V and 16V, it operates in passthru mode with the boost synchronous FET fully on and the buck in drop-out with >99% duty cycle. When VIN is below 10V, the boost is activated and when VIN is above 16V, the buck is activated as shown in Figure 4b. The LT7812 data sheet gives a complete description of the part, operation and application information and must be read in conjunction with this quick start guide. Design files for this circuit board are available at http://www.linear.com/demo/DC2422A L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Specifications are at TA = 25°C CONDITIONS MIN Input Supply Range Output1 Voltage Range = 0A to 8A† 11.7 DC2422A-B: VIN = 4V* – 36V, IOUT1 = 0A to 8A† 9.7 DC2422A-A: VIN = 4V* – 36V, IOUT1 DC2422A-C: VIN = 4V* – 36V, IOUT1 = 0A to 8A† VBUS VBUS Voltage Range (DC2422A-C only) fSW Typical Free Running Switching Frequency Efficiency See Figures 3, 4, 5 and 6 for Efficiency Curves TYP 4 MAX 36 12 UNITS V 12.3 V 16.3 V 4.9 5** 5.1 V 11.7 12 12.3 V 350 kHz DC2422A-A:VIN = 8V, VOUT1 = 12V, IOUT1 = 8A VIN = 12V, VOUT1 = 12V, IOUT1 = 8A VIN = 36V, VOUT1 = 12V, IOUT1 = 8A 93 95.4 95 % % % DC2422A-B:VIN = 8V, VOUT1 = 10V, IOUT1 = 8A VIN = 12V, VOUT1 = 12V, IOUT1 = 8A VIN = 36V, VOUT1 = 16V, IOUT1 = 6A 94.8 97.2 95.8 % % % DC2422A-C:VIN = 8V, VBUS = 12V, Ibus = 8A VIN = 12V, VOUT1 = 5V, IOUT1 = 8A VIN = 36V, VOUT1 = 5V, IOUT1 = 8A 95.8 94 91.9 % % % †I OUT1 starts to derate when VIN < 8V, *VIN needs to be >4.5V to start up, **VOUT1 follows VIN when VIN < 5V. dc2422af 1 DEMO MANUAL DC2422A-A, DC2422A-B, DC2422A-C QUICK START PROCEDURE Demonstration circuit DC2422A is easy to set up to evaluate the performance of the LTC7812EUH. Refer to Figure 1 for proper measurement equipment setup and follow the procedure below: 3. Turn on the power at the input. NOTE: Make sure that the input voltage is higher than 8V and does not exceed 36V. 4. Check for the proper output voltages for different boards. NOTE: When measuring the input or output voltage ripple, care must be taken to avoid a long ground lead on the oscilloscope probe. Measure the input or output voltage ripple by touching the probe tip directly across the VIN or VOUT and GND terminals or directly across relevant capacitor. See Figure 2 for proper scope probe technique. DC2422A-B:9.7V < VOUT1 < 16.3V, 1. Place jumpers in the following positions: NOTE: If there is no output, temporarily disconnect the load to make sure that the load is not set too high. JP1: ON JP2: ON JP3: Burst Mode BURST 2. With power off, connect the input power supply to VIN and GND. DC2422A-A: VOUT1 = 11.7V to 12.3V, DC2422A-C: VOUT1 = 4.9V to 5.1V; VBUS = 11.7V to 12.3V. 5. Once the proper output voltages are established, adjust the loads within the operating range and observe the output voltage regulation, ripple voltage, efficiency and other parameters. IOUT – – + IOUT LOAD + – – LOAD + + IIN + – + VIN SUPPLY – Figure 1. Proper Measurement Equipment Setup dc2422af 2 DEMO MANUAL DC2422A-A, DC2422A-B, DC2422A-C QUICK START PROCEDURE + COUT VOUT – GND Figure 2. Measuring Input or Output Ripple Directly Across Ceramic Capacitor FREQUENCY SYNCHRONIZATION AND MODE SELECTION Demonstration circuit DC2422A’s Mode selector allows the converter to run in forced continuous operation, pulse skip operation, Burst Mode operation or be synchronizing to an external clock by changing the position of JP3. Table 1. Mode Selection and Synchronized Operation Options CONFIGURATION JP3 Forced Continuous Operation FCM Pulse Skip Operation PS/Sync Synchronized to Ext. Clock Applied to CLKIN Pin PS/Sync Burst Mode Operation Burst RAIL TRACKING Demonstration circuit DC2422A is configured for an onboard soft-start circuit. The soft-start ramp rate can be adjusted by changing the value of C47. Demonstration circuit DC2422A can also be modified to track an external reference. Refer to Table 2 for tracking options and to the data sheet for more details. Table 2. VOUT1 Tracking Options CONFIGURATION Soft-Start without Tracking (Default) VOUT1 Tracking Scaled External Reference R34 R37 OPEN OPEN Resistor Divider C47 TRK/SS1 CAP 0.1µF OPEN OPEN External Reference OPTIONAL INDUCTOR DCR CURRENT SENSING Demonstration circuit 2422A provides an optional circuit for Inductor DCR Current Sensing. Inductor DCR Current Sensing uses the DCR of the inductor to sense the inductor current instead of discrete sense resistors. The advantages of DCR sensing are lower cost, reduced board space and higher efficiency, but the disadvantage is a less accurate current limit. If DCR sensing is used, be sure to select an inductor current with a sufficiently high saturation current or use an iron powder type material. Refer to Table 3 for Optional Inductor DCR Current Sensing setup and to the data sheet for more details. dc2422af 3 DEMO MANUAL DC2422A-A, DC2422A-B, DC2422A-C OPTIONAL INDUCTOR DCR CURRENT SENSING Table 3. Optional Inductor DCR Current Sensing CHANNEL1 CONFIGURATION RS1 CHANNEL2 Current Sense Resistor (Default) Inductor DCR Current Sensing R39 R40 C15 R51 R53 R62 RS2 R80 R81 C56 R89 R90 R91 Ref. Sch. Ref. Sch. Ref. Sch. Ref. Sch. OPEN OPEN OPEN 0Ω Copper OPEN OPEN Low Quiescent Current Applications and Measurement The typical quiescent current (IQ) of the LTC7812 controller is 28µA in sleep mode as specified in the LTC7812 data sheet. However, the input current of the DC2422A board can be higher than this value because of additional circuit outside of the IC. To reduce the total input current, large value FB divider resistors should be used. In addition, some 100 Calculated Value from Data Sheet 0Ω of the optional pull-up resistors should be removed from the board. Refer to Table 4 for the low input quiescent current setup. Table 4. Low Input Quiescent Current Configuration Reference Designator R46 Function Stuffing Option R92 PGOOD1 OV2 OPEN OPEN VOUT1 = 12V EFFICIENCY 90 EFFICIENCY (%) 80 70 60 50 VIN = 8V BURST VIN = 36V BURST VIN = 8V FCM VIN = 36V FCM 40 30 0.1 1 IOUT (A) 10 dc2422a F03 Figure 3. DC2422A-A VOUT1 Typical Efficiency vs Load Current VOUT1 100 90 VOUT = VIN VBUCK EFFICIENCY (%) 80 70 VBOOST 60 BUCK ACTIVE PASS-THRU WIRE MODE 50 VIN = 12V VIN = 8V VIN = 36V 40 30 0.1 1 IOUT (A) BOOST ACTIVE 10 10V 16V dc2422a F04b VIN dc2422a F04a Figure 4a. DC2422A-B VOUT1 Typical FCM Efficiency vs Load Current Figure 4b. DC2422A-B Partially Regulated VOUT dc2422af 4 DEMO MANUAL DC2422A-A, DC2422A-B, DC2422A-C OPTIONAL INDUCTOR DCR CURRENT SENSING 100 95 100 VIN = 8V, VBUS = 12V EFFICIENCY 90 80 85 EFFICIENCY (%) EFFICIENCY (%) 90 80 75 70 65 60 50 60 PULSE SKIP BURST FCM 55 50 0.1 70 1 IOUT (A) 10 30 0.1 dc2422a F05 20MHz BW 20mV/DIV 20mV/DIV dc2422 F07 Figure 7. DC2422A-A VOUT1 Voltage Ripple at VIN = 8V 5µs/DIV 20MHz BW 20mV/DIV 50mV/DIV Figure 9. DC2422A-A VOUT1 2A – 4A – 2A Load Transient at VIN = 8V 10 dc2422a F06 dc2422 F08 Figure 8. DC2422A-A VOUT1 Voltage Ripple at VIN = 36V 20MHz BW dc2422 F09 1 IOUT (A) Figure 6. DC2422A-C VOUT1 Typical Efficiency vs Load Current 20MHz BW 200µs/DIV VIN = 8V BURST VIN = 36V BURST VIN = 8V FCM VIN = 36V FCM 40 Figure 5. DC2422A-C VBUS Typical Efficiency vs Load Current 5µs/DIV VOUT1 = 5V EFFICIENCY 200µs/DIV dc2422 F10 Figure 10. DC2422A-A VOUT1 2A – 4A – 2A Load Transient at VIN = 36V dc2422af 5 DEMO MANUAL DC2422A-A, DC2422A-B, DC2422A-C PARTS LIST ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER DC2422A-A Required Circuit Components 1 1 CIN1 CAP, 33µF, 63V, 20%, ELEC SUN ELEC. 63HVH33M 2 1 COUT1 CAP, 100µF, 50V, 20%, ELEC PANASONIC, EEHZA1H101P 3 6 CIN2, CIN3, CIN4, COUT6, COUT8, C59, C80 CAP, 10µF, X7R, 50V, 10%, 1210 AVX, 12105C106KAT2A 4 1 COUT4 CAP, 4.7µF, X7R, 16V, 20%, 1206 TDK, C3216X7R1C475M 5 2 COUT5, COUT11 CAP, 150µF, 16V, 20% 7343 PANASONIC, 16TQC150MYF 6 5 C4, C17, C21, C47, C52 CAP, 0.1µF, X7R, 25V, 10%, 0603 TDK, C1608X7R1E104K 7 2 C5, C51 CAP, 4.7µF, X5R, 50V, 10%, 0805 TDK, C2012X5R1H475K125AB 8 4 C15, C53, C56, C62 CAP, 1nF, X7R, 50V, 10%, 0603 AVX, 06035C102KAT2A 9 1 C43 CAP, 68pF, NPO, 50V, 10%, 0603 AVX, 06035A680KAT2A 10 1 C44 CAP, 2.2nF, X7R, 50V, 10%, 0603 AVX, 06035C222KAT2A 11 1 C54 CAP, 10nF, X7R, 50V, 10%, 0603 TDK, C1608X7R1H103K 12 1 C61 CAP, 1µF, X5R, 25V, 20%, 0603 TDK, C1608X5R1E105M 13 1 C64 CAP, 4.7µF X5R, 10V, 20%, 0603 AVX, 0603ZD475MAT2A 14 2 D1, D2 DIODE, SCHOTTKY, 40V, 3A, SOD323 CENTRAL SEMI, CMDSH-4E 15 0 D3 DIODE, SCHOTTKY, 40V, 3A, SMB DIODES INC, B340B-13-F OPTION 16 0 L1 IND, 4.7µH COILCRAFT, XAL7070-472 17 0 L2 IND, 1.0µH COILCRAFT, XAL7070-102 18 2 Q1, Q2 XSTR, N-CHANNEL MOSFET INFINEON, BSC093N04LS 19 2 Q21, Q22 XSTR, N-CHANNEL MOSFET INFINEON, BSC027N04LS 20 1 RS1 RES., SENSE, 0.003Ω, 1/2W, 1%, 2010 VISHAY, WSL20103L000FEA 21 2 RS2, RS3 RES., SENSE, 0.004Ω, 1/2W, 1%, 2010 VISHAY, WSL20104L000FEA 22 1 R33 RES., 35.7k, 1/10W, 1%, 0603 VISHAY, CRCW060335K7FKEA 23 1 R35 RES., 15k, 1/10W, 5%, 0603 VISHAY, CRCW060315K0JNEA 24 1 R43 RES., 499k, 1/10W, 1%, 0603 VISHAY, CRCW0603499KFKEA 25 3 R46, R48, R92 RES., 100k, 1/10W, 5%, 0603 VISHAY, CRCW0603100KJNEA 26 1 R75 RES., 3.6k, 1/10W, 1%, 0603 VISHAY, CRCW06033K60FKEA 27 1 R78 RES., 549k, 1/10W, 1%, 0603 VISHAY, CRCW0603549KFKEA 28 1 R79 RES., 49.9k, 1/10W, 1%, 0603 VISHAY, CRCW060349K9FKEA 29 1 R81 RES., 100Ω, 1/10W, 5%, 0603 VISHAY, CRCW0603100RJNEA 30 1 R86 RES., 2.2Ω, 1/10W, 5%, 0603 VISHAY, CRCW06032R20JNEA 31 1 U1 IC, LOW IQ, 38V BOOST + BUCK SYNCHRONOUS CONTROLLER LINEAR TECH. LTC7812EUH#PBF dc2422af 6 DEMO MANUAL DC2422A-A, DC2422A-B, DC2422A-C PARTS LIST ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER Additional Demo Board Circuit Components 1 0 C1, C2, C3, C6, CIN5, C68 CAP, OPTION, 1210 OPTION 2 0 COUT2 CAP, OPTION OPTION 3 0 C36 CAP, OPTION, 1206 OPTION 4 0 C39, C40, C66, C67, C73, C74, C78, C79 CAP, OPTION, 0805 OPTION 5 0 C49, C55, C57, C60, C63, C65, C77 CAP, OPTION, 0603 OPTION 6 0 L3 IND, OPTION COILCRAFT, OPTION 7 0 Q9, Q11, Q18, Q19 XSTR, N-CHANNEL MOSFET OPTION 8 9 R34, R36, R39, R40, R70, R72, R80, R95, R96 RES., 0Ω, 1/10W, 0603 VISHAY, CRCW06030000Z0EA 9 0 R37, R51, R53, R55, R62, R85, R89, R90, R91, R93, R94 RES., OPTION, 0603 OPTION 10 0 R82 RES., OPTION, 1206 OPTION 11 0 R100 RES., OPTION , 0805 OPTION 12 0 R101 RES., OPTION, 1210 OPTION 13 1 R102 RES., 0Ω, 2010 VISHAY, CRCW20100000Z0EF Hardware: For Demo Board Only 1 15 E1-E15 TURRET MILL-MAX, 2501-2-00-80-00-00-07-0 2 2 JP1, JP2 CONN., HEADER, 1X3, 2mm WURTH ELEKTRONIK, 620 003 111 21 3 1 JP3 CONN., HEADER, 2X3, 2mm WURTH ELEKTRONIK, 620 006 211 21 4 3 XJP1, XJP2, XJP3 SHUNT, 2mm WURTH ELEKTRONIK, 608 002 134 21 5 6 J1, J2, J3, J4, J5, J6 JACK, BANANA KEYSTONE, 575-4 6 4 STANDOFF, SNAP ON KEYSTONE, 8833 dc2422af 7 DEMO MANUAL DC2422A-A, DC2422A-B, DC2422A-C PARTS LIST ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER SUN ELEC. 63HVH33M DC2422A-B Required Circuit Components 1 1 CIN1 CAP, 33µF, 63V, 20%, ELEC 2 1 COUT1 CAP, 100µF, 50V, 20%, ELEC PANASONIC, EEHZA1H101P 3 6 CIN2, CIN3, CIN4, COUT6, COUT8, C59, C80 CAP, 10µF, X7R, 50V, 10%, 1210 AVX, 12105C106KAT2A 4 1 COUT4 CAP, 4.7µF, X7R, 16V, 20%, 1206 TDK, C3216X7R1C475M 5 2 COUT5, COUT11 CAP, 150µF, 16V, 20% 7343 PANASONIC, 16TQC150MYF 6 5 C4, C17, C21, C47, C52 CAP, 0.1µF, X7R, 25V, 10%, 0603 TDK, C1608X7R1E104K 7 2 C5, C51 CAP, 4.7µF, X5R, 50V, 10%, 0805 TDK, C2012X5R1H475K125AB 8 4 C15, C53, C56, C62 CAP, 1nF, X7R, 50V, 10%, 0603 AVX, 06035C102KAT2A 9 1 C43 CAP, 68pF, NPO, 50V, 10%, 0603 AVX, 06035A680KAT2A 10 1 C44 CAP, 2.2nF, X7R, 50V, 10%, 0603 AVX, 06035C222KAT2A 11 1 C54 CAP, 10nF, X7R, 50V, 10%, 0603 TDK, C1608X7R1H103K 12 1 C61 CAP, 1µF, X5R, 25V, 20%, 0603 TDK, C1608X5R1E105M 13 1 C64 CAP, 4.7µF X5R, 10V, 20%, 0603 AVX, 0603ZD475MAT2A 14 2 D1, D2 DIODE, SCHOTTKY, 40V, 3A, SOD323 CENTRAL SEMI, CMDSH-4E 15 0 D3 DIODE, SCHOTTKY, 40V, 3A, SMB DIODES INC, B340B-13-F OPTION 16 0 L1 IND, 4.7µH COILCRAFT, XAL7070-472 17 0 L2 IND, 1.0µH COILCRAFT, XAL7070-102 18 2 Q1, Q2 XSTR, N-CHANNEL MOSFET INFINEON, BSC093N04LS 19 2 Q21, Q22 XSTR, N-CHANNEL MOSFET INFINEON, BSC027N04LS 20 1 RS1 RES., SENSE, 0.003Ω, 1/2W, 1%, 2010 VISHAY, WSL20103L000FEA 21 2 RS2, RS3 RES., SENSE, 0.004Ω, 1/2W, 1%, 2010 VISHAY, WSL20104L000FEA 22 1 R33 RES., 26.7k, 1/10W, 1%, 0603 VISHAY, CRCW060326K7FKEA 23 1 R35 RES., 15k, 1/10W, 5%, 0603 VISHAY, CRCW060315K0JNEA 24 1 R43 RES., 499k, 1/10W, 1%, 0603 VISHAY, CRCW0603499KFKEA 25 3 R46, R48, R92 RES., 100k, 1/10W, 5%, 0603 VISHAY, CRCW0603100KJNEA 26 1 R75 RES., 3.6k, 1/10W, 1%, 0603 VISHAY, CRCW06033K60FKEA 27 1 R78 RES., 365k, 1/10W, 1%, 0603 VISHAY, CRCW0603365KFKEA 28 1 R79 RES., 49.9k, 1/10W, 1%, 0603 VISHAY, CRCW060349K9FKEA 29 1 R81 RES., 100Ω, 1/10W, 5%, 0603 VISHAY, CRCW0603100RJNEA 30 1 R86 RES., 2.2Ω, 1/10W, 5%, 0603 VISHAY, CRCW06032R20JNEA 31 1 U1 IC, LOW IQ, 38V BOOST + BUCK SYNCHRONOUS CONTROLLER LINEAR TECH. LTC7812EUH#PBF dc2422af 8 DEMO MANUAL DC2422A-A, DC2422A-B, DC2422A-C PARTS LIST ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER Additional Demo Board Circuit Components 1 0 C1, C2, C3, C6, CIN5, C68 CAP, OPTION, 1210 OPTION 2 0 COUT2 CAP, OPTION OPTION 3 0 C36 CAP, OPTION, 1206 OPTION 4 0 C39, C40, C66, C67, C73, C74, C78, C79 CAP, OPTION, 0805 OPTION 5 0 C49, C55, C57, C60, C63, C65, C77 CAP, OPTION, 0603 OPTION 6 0 L3 IND, OPTION COILCRAFT, OPTION 7 0 Q9, Q11, Q18, Q19 XSTR, N-CHANNEL MOSFET OPTION 8 9 R34, R36, R39, R40, R70, R72, R80, R95, R96 RES., 0Ω, 1/10W, 0603 VISHAY, CRCW06030000Z0EA 9 0 R37, R51, R53, R55, R62, R85, R89, R90, R91, RES., OPTION, 0603 R93, R94 OPTION 10 0 R82 RES., OPTION, 1206 OPTION 11 0 R100 RES., OPTION, 0805 OPTION 12 0 R101 RES., OPTION, 1210 OPTION 13 1 R102 RES., 0Ω, 2010 VISHAY, CRCW20100000Z0EF Hardware: For Demo Board Only 1 15 E1-E15 TURRET MILL-MAX, 2501-2-00-80-00-00-07-0 2 2 JP1, JP2 CONN., HEADER, 1X3, 2mm WURTH ELEKTRONIK, 620 003 111 21 3 1 JP3 CONN., HEADER, 2X3, 2mm WURTH ELEKTRONIK, 620 006 211 21 4 3 XJP1, XJP2, XJP3 SHUNT, 2mm WURTH ELEKTRONIK, 608 002 134 21 5 6 J1, J2, J3, J4, J5, J6 JACK, BANANA KEYSTONE, 575-4 6 4 STANDOFF, SNAP ON KEYSTONE, 8833 dc2422af 9 DEMO MANUAL DC2422A-A, DC2422A-B, DC2422A-C PARTS LIST ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER DC2422A-C Required Circuit Components 1 1 CIN1 CAP, 33µF, 63V, 20%, ELEC SUN ELEC. 63HVH33M 2 1 COUT1 CAP, 100µF, 50V, 20%, ELEC PANASONIC, EEHZA1H101P 3 6 CIN2, CIN3, CIN4, COUT6, COUT8, C59, C80 CAP, 10µF, X7R, 50V, 10%, 1210 AVX, 12105C106KAT2A 4 1 COUT4 CAP, 4.7µF, X7R, 16V, 20%, 1206 TDK, C3216X7R1C475M 5 2 COUT5, COUT11 CAP, 150µF, 16V, 20% 7343 PANASONIC, 16TQC150MYF 6 5 C4, C17, C21, C47, C52 CAP, 0.1µF, X7R, 25V, 10%, 0603 TDK, C1608X7R1E104K 7 2 C5, C51 CAP, 4.7µF, X5R, 50V, 10%, 0805 TDK, C2012X5R1H475K125AB 8 4 C15, C53, C56, C62 CAP, 1nF, X7R, 50V, 10%, 0603 AVX, 06035C102KAT2A 9 1 C43 CAP, 68pF, NPO, 50V, 10%, 0603 AVX, 06035A680KAT2A 10 1 C44 CAP, 2.2nF, X7R, 50V, 10%, 0603 AVX, 06035C222KAT2A 11 1 C54 CAP, 10nF, X7R, 50V, 10%, 0603 TDK, C1608X7R1H103K 12 1 C61 CAP, 1µF, X5R, 25V, 20%, 0603 TDK, C1608X5R1E105M 13 1 C64 CAP, 4.7µF X5R, 10V, 20%, 0603 AVX, 0603ZD475MAT2A 14 2 D1, D2 DIODE, SCHOTTKY, 40V, 3A, SOD323 CENTRAL SEMI, CMDSH-4E 15 0 D3 DIODE, SCHOTTKY, 40V, 3A, SMB DIODES INC, B340B-13-F OPTION 16 0 L1 IND, 4.7µH COILCRAFT, XAL7070-472 17 0 L2 IND, 1.0µH COILCRAFT, XAL7070-102 18 2 Q1, Q2 XSTR, N-CHANNEL MOSFET INFINEON, BSC093N04LS 19 2 Q21, Q22 XSTR, N-CHANNEL MOSFET INFINEON, BSC027N04LS 20 1 RS1 RES., SENSE, 0.003Ω, 1/2W, 1%, 2010 VISHAY, WSL20103L000FEA 21 2 RS2, RS3 RES., SENSE, 0.004Ω, 1/2W, 1%, 2010 VISHAY, WSL20104L000FEA 22 1 R33 RES., 68.1k, 1/10W, 1%, 0603 VISHAY, CRCW060368K1FKEA 23 1 R35 RES., 15k, 1/10W, 5%, 0603 VISHAY, CRCW060315K0JNEA 24 1 R43 RES., 357k, 1/10W, 1%, 0603 VISHAY, CRCW0603357KFKEA 25 3 R46, R48, R92 RES., 100k, 1/10W, 5%, 0603 VISHAY, CRCW0603100KJNEA 26 1 R75 RES., 3.6k, 1/10W, 1%, 0603 VISHAY, CRCW06033K60FKEA 27 1 R78 RES., 453k, 1/10W, 1%, 0603 VISHAY, CRCW0603453KFKEA 28 1 R79 RES., 49.9k, 1/10W, 1%, 0603 VISHAY, CRCW060349K9FKEA 29 1 R81 RES., 100Ω, 1/10W, 5%, 0603 VISHAY, CRCW0603100RJNEA 30 1 R86 RES., 2.2Ω, 1/10W, 5%, 0603 VISHAY, CRCW06032R20JNEA 31 1 U1 IC, LOW IQ, 38V BOOST + BUCK SYNCHRONOUS CONTROLLER LINEAR TECH. LTC7812EUH#PBF dc2422af 10 DEMO MANUAL DC2422A-A, DC2422A-B, DC2422A-C PARTS LIST ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER Additional Demo Board Circuit Components 1 0 C1, C2, C3, C6, CIN5, C68 CAP, OPTION, 1210 OPTION 2 0 COUT2 CAP, OPTION OPTION 3 0 C36 CAP, OPTION, 1206 OPTION 4 0 C39, C40, C66, C67, C73, C74, C78, C79 CAP, OPTION, 0805 OPTION 5 0 C49, C55, C57, C60, C63, C65, C77 CAP, OPTION, 0603 OPTION 6 0 L3 IND, OPTION COILCRAFT, OPTION 7 0 Q9, Q11, Q18, Q19 XSTR, N-CHANNEL MOSFET OPTION 8 9 R34, R36, R39, R40, R70, R72, R80, R95, R96 RES., 0Ω, 1/10W, 0603 VISHAY, CRCW06030000Z0EA 9 0 R37, R51, R53, R55, R62, R85, R89, R90, R91, R93, R94, R100 RES., OPTION, 0603 OPTION 10 0 R82 RES., OPTION, 1206 OPTION 11 1 R101 RES., 0Ω, 2010 VISHAY, CRCW20100000Z0EF 12 0 R102 RES., OPTION, 1210 OPTION Hardware: For Demo Board Only 1 15 E1-E15 TURRET MILL-MAX, 2501-2-00-80-00-00-07-0 2 2 JP1, JP2 CONN., HEADER, 1X3, 2mm WURTH ELEKTRONIK, 620 003 111 21 3 1 JP3 CONN., HEADER, 2X3, 2mm WURTH ELEKTRONIK, 620 006 211 21 4 3 XJP1, XJP2, XJP3 SHUNT, 2mm WURTH ELEKTRONIK, 608 002 134 21 5 6 J1, J2, J3, J4, J5, J6 JACK, BANANA KEYSTONE, 575-4 6 4 STANDOFF, SNAP ON KEYSTONE, 8833 dc2422af 11 D C B A OFF E12 E11 0 JP1 3 2 1 R37 OPT R46 100K INTVCC R34 RUN1 ON E10 E9 VOUT1 OFF JP2 RUN2 ON 0 C77 OPT * R36 R33 3 2 1 OPT C49 R43 1 2 1. ALL RESISTORS AND CAPACITORS ARE 0603. NOTE: UNLESS OTHERWISE SPECIFIED PGOOD1 RUN2 RUN1 TRACK / SS1 FREQ E8 C60 OPT VBUS * 0 R70 68pF 1nF C47 0.1uF 10nF C54 C53 15K R35 C43 R78 * C55 OPT R72 0 R94 OPT INTVCC 11 4 15 5 3 JP3 R33 35.7K 26.7K 68.1K SGND PGOOD1 RUN2 RUN1 SS2 TRK/SS1 ITH2 ITH1 VFB2 VFB1 FREQ BURST PS/SYNC FCM R43 499K 499K 357K * C64 4.7uF R80 0 4 4 R81 100 OPT C63 BOOST1 32 S1- 8 TG2 29 R102 0 0 OPT BG2 SW2 30 27 BOOST2 28 25 S1+ 7 EXTVCC BG1 31 1 TG1 R39 0 0 R95 0 R96 C17 0.1uF VBIAS C62 1nF INTVCC 2 26 23 18 20 21 22 R101 OPT OPT 0 BG2 TG2 SW2 BOOST2 EXTVCC SENSE1- SENSE1+ BG1 SW1 BOOST1 TG1 VBIAS N/C SGND SGND SGND OV2 R48 100K INTVCC R78 549K 365K 453K 1nF C56 U1 LTC7812EUH 6 4 2 PLLIN/MODE ASSY VOUT1 ‐A 12V ‐B 12V ‐C 5V 16 3 RUN2 19 RUN1 17 0.1uF C52 SS2 SS1 R75 3.6K ITH2 ITH1 C44 2.2nF 6 14 R79 49.9K VFB2 VFB1 9 10 5 3 1 INTVCC INTVCC 24 CLKIN MODE PGND 33 3 SENSE2+ S2+ 12 E7 2 SENSE213 S2- C4 0.1uF 1nF C15 5 INTVCC 4 * R102 2010 OPT C57 VIN 6 THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. DL SCALE = NONE LT PCB DES. 7 DATE: N/A TECHNOLOGY ** CIN4 10uF 50V 1210 COUT11 150uF 16V 7343 CIN5 OPT 1210 100uF 50V + + COUT1 VIN COUT8 10uF 50V 1210 VBUS COUT5 150uF 16V 7343 CIN1 33uF 63V J2 J1 J6 E2 E1 COUT2 OPT E6 E5 GND VBUS GND ** VIN- GND VIN VIN+ GND GND VBUS E4 VOUT1 VOUT1 7 IC NO. * Tuesday, September 08, 2015 8 SHEET 1 LTC7812EUH DEMO CIRCUIT 2422A OF 2 REV. 2 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only + + J5 C36 OPT 1206 J4 J3 E3 SHT 2 OV2 DL APPROVED WIDE VIN, STEP UP/DOWN POWER SUPPLY TITLE: SCHEMATIC SIZE + 4~36VIN VBUSFOLLOWSVINWHEN VIN>VBUSSETVOLTAGE DERATEIOUT@VIN<8V CIN3 10uF 50V 1210 COUT6 10uF 50V 1210 COUT4 4.7uF 16V 1206 VOUT1 VBUS_ BG2 TG2 BG1 S2- VL2- TG1 S2+ S1- VSW2 VL1- E13 9/08/15 DATE 8 S1+ SHT 2 PRODUCTION SHT 2 REVISION HISTORY DESCRIPTION VSW1 C78 TBD 0805 CIN2 10uF 50V 1210 C5 4.7uF 50V 0805 0.003 C6 OPT 1210 APP ENG. 2 - C79 TBD 0805 REV ECO RS1 C59 10uF 50V 1210 APPROVALS RS3 0.004 RS2 0.004 C3 OPT 1210 4.7uH VL1- C51 4.7uF 50V 0805 L1 VL2- C2 OPT 1210 VSW1 1.0uH R82 OPT L2 CUSTOMER NOTICE VSW2 Q2 BSC093N04LS C1 OPT 1210 * 2010 R101 VBUS 6 LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. 4 4 Q21 BSC027N04LS INTVCC Q22 BSC027N04LS CMDSH-4E D2 R40 0 D1 4 Q1 BSC093N04LS C21 0.1uF CMDSH-4E R92 100K INTVCC 5 5 6 7 8 1 2 3 5 6 7 8 1 2 3 5 6 7 8 1 2 3 5 6 7 8 12 1 2 3 1 D C B A DEMO MANUAL DC2422A-A, DC2422A-B, DC2422A-C SCHEMATIC DIAGRAM dc2422af VIN E15 C39 OPT 0805 SGND EXTVCC E14 C40 OPT 0805 R55 OPT EXTVCC C73 TBD 0805 VBUS C61 1uF OPT R93 C74 TBD 0805 VOUT1 SHT 1 SHT 1 S1- VSW1 Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. VSW1 BG1 SHT 1 SHT 1 BG1 VSW1 TG1 4 4 Q19 OPT OPT R62 VIN VBUS S1- R53 OPT VL1- S1+ Q18 OPT VIN THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. L3 SCALE = NONE DL LT APPROVALS BG2 VSW2 TG2 TBD DATE: N/A SIZE 4 Q9 OPT OPT R91 TECHNOLOGY 4 C67 TBD 0805 S2+ R90 OPT C68 TBD 1210 VL2- S2- D3 OPT GND VIN_EMI IC NO. Tuesday, September 08, 2015 SHEET 2 LTC7812EUH DEMO CIRCUIT 2422A 2 OF 2 REV. 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only Q11 OPT VBUS J10 J9 VL2- SHT 1 S2- SHT 1 WIDE VIN, STEP UP/DOWN POWER SUPPLY TITLE: SCHEMATIC BG2 VSW2 SHT 1 TBD 0805 TG2 SHT 1 OPT R89 TBD C65 R100 VSW2 SHT 1 C66 TBD 0805 SHT 1 S2+ SHT 1 VSW2 C80 10uF 50V 1210 VL1- SHT 1 S1+ SHT 1 LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO PCB DES. VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED APP ENG. CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. CUSTOMER NOTICE TG1 SHT 1 SHT 1 2.2 OPT R86 R85 VBUS_ OPT R51 VBIAS VSW1 WHEN DCR SENSING IS IMPLEMENTED,SHORT RS1 & RS2. REMOVE R30, R29, R80 & R81.STUFF R62 AND R91 WITH 0 OHMS. CALCULATE R51, R53 & C15 AND R89, R90 & C56 PER THE DATA SHEET. ALSO REFER TO QSG FOR EXAMPLE. NOTE: 5 6 7 8 1 2 3 5 6 7 8 1 2 3 5 6 7 8 1 2 3 5 6 7 8 1 2 3 1 2 OPTIONAL DCR SENSING DEMO MANUAL DC2422A-A, DC2422A-B, DC2422A-C SCHEMATIC DIAGRAM dc2422af 13 DEMO MANUAL DC2422A-A, DC2422A-B, DC2422A-C DEMONSTRATION BOARD IMPORTANT NOTICE Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions: This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use. As such, the DEMO BOARD herein may not be complete in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations. If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual the kit may be returned within 30 days from the date of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY THE SELLER TO BUYER AND IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES. The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user releases LTC from all claims arising from the handling or use of the goods. Due to the open construction of the product, it is the user’s responsibility to take any and all appropriate precautions with regard to electrostatic discharge. Also be aware that the products herein may not be regulatory compliant or agency certified (FCC, UL, CE, etc.). No License is granted under any patent right or other intellectual property whatsoever. LTC assumes no liability for applications assistance, customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind. LTC currently services a variety of customers for products around the world, and therefore this transaction is not exclusive. Please read the DEMO BOARD manual prior to handling the product. Persons handling this product must have electronics training and observe good laboratory practice standards. Common sense is encouraged. This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LTC application engineer. Mailing Address: Linear Technology 1630 McCarthy Blvd. Milpitas, CA 95035 Copyright © 2004, Linear Technology Corporation dc2422af 14 Linear Technology Corporation LT 1115 • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com © LINEAR TECHNOLOGY CORPORATION 2015