CBM2596DT-ADJ

CBM2596-XX OPERATION INSTRUCTION FEATURES  3.3V, 5V, 12V, and adjustable output GENERAL DESCRIPTION versions  Adjustable version output voltage range, The CBM2596 series of regulators are 1.2V to 37V± 4% max over line and load monolithic integrated circuits that provide all conditions the active functions for a step-down switching  Guaranteed 3A output load current  Input voltage range up to 40V  Requires only 4 external components  Excellent line and load regulation regulator, capable of driving a 3A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5V, 12V and an adjustable output version. specifications Requiring a minimum number of external  150kHz fixed frequency internal oscillator components, these regulators are simple to  TTL shutdown capability use.  Low power standby mode, The series operates at a switching frequency of 150kHz. Available in IQ typically 100μA  CBM2596 standard 5-lead TO-220 package. Thermal shutdown and current limit Other features include a guaranteed ± 4% protection tolerance on output voltage under specified input voltage and output load conditions, and ± 15% on the oscillator frequency. External APPLICATIONS shutdown is included, featuring typically Simple high-efficiency step-down 100μA standby current. regulator features include a two  On-card switching regulators reducing current limit for output switch and  Positive to negative converter  Self protection stage frequency an over temperature shutdown for complete protection under fault conditions. The over temperature shutdown level is about 145℃ with 5℃ hysteresis. ABSOLUTE MAXIMUM RATINGS 1 www.corebai.com CBM2596-XX OPERATION INSTRUCTION (Absolute Maximum Ratings indicate limits beyond which damage to the device may occur.) Rating Symbol Value Unit Maximum Input Supply Voltage VI 45V V ON/OFF Pin Input Voltage VIN -0.3V≤V≤+25V V Feedback Pin Voltage - -0.3V≤V≤+25V V Output Voltage to Ground VO -1V V Power Dissipation PD Internally limited W Storage Temperature Range Tstg -65℃ to +150℃ ℃ Operating Temperature Range TJ 40℃≤TJ≤+125℃ ℃ Operating Supply Voltage VIN 4.5V to 40V V * Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. Typical Aplication (Fixed Output Voltage Versions) ELECTRICAL CHARACTERISTICS Unless otherwise specified, TJ = 25℃，VIN = 12V for the 3.3V, 5V, and Adjustable version and VIN = 24V for the 12V version. ILOAD = 500mA. 2 www.corebai.com CBM2596-XX OPERATION INSTRUCTION Characteristic Symbol Test Condition CBM2596–3 Output Voltage VOUT CBM2596–5 CBM2596–12 Efficiency η 4.75V≤VIN≤40V, 0.2A≤ILOAD≤3A 7V≤VIN≤40V, 0.2A≤ILOAD≤3A 15V≤VIN≤40V, 0.2A≤ILOAD≤3A Min Typ Max 3.168 3.3 3.432 4.8 5.0 5.2 11.52 12.0 12.48 CBM2596–3 ILOAD = 3A 73 CBM2596–5 ILOAD = 3A 80 CBM2596–12 VIN = 25V, ILOAD = 3A 90 CBM2596–A VOUT = 3V, ILOAD = 3A 73 Unit V % 4.5V≤VIN≤40V, Feedback Voltage VFB CBM2596–A 0.2A≤ILOAD≤3A VOUT 1.193 1.230 1.267 V 15 50 nA 150 173 kHz IOUT = 3A(Note 1,2) 1.16 1.4 V (Note 2) 100 programmed for 3V Feedback Bias Current Oscillator Frequency Saturation Voltage ID Max Duty Cycle VSAT Output Leakage Current Quiescent Current Standby Quiescent 110 DC % (Note 3) (OFF) Current Limit VFB = 1.3V fO Max Duty Cycle (ON) CBM2596-A ICL IL IQ 0 Peak Current(Note 1,2) 3.4 4.5 Output = 0V(Note 1,3) 6.0 A 50 μA Output = -1V, VIN = 40V 2 30 mA (Note 3) 5 10 mA 100 200 μA 1.3 0.6 ISTBY ON/OFF pin = 5V (OFF), VIN = 40V VIH Low (Regulator ON) Threshold Voltage VIL High (Regulator OFF) ON/OFF Pin Input IH VLOGIC = 2.5V (regulator OFF) 5 15 Current IL VLOGIC = 0.5V (regulator ON) 0.02 5 Current ON/OFF Pin Logic 2.0 Input V μA Note 1: No elements connected to output pin. Note 2: Feedback pin removed from output and connected to 0V to force the output transistor switch ON. Note 3: Feedback pin removed from output and connected to 12V for the 3.3V, 5V, and the A version, and 15V for the 12V version. To force the output transistor switch OFF. Typical Perfomance Characteristics 3 www.corebai.com CBM2596-XX OPERATION INSTRUCTION 4 www.corebai.com CBM2596-XX OPERATION INSTRUCTION 5 www.corebai.com CBM2596-XX OPERATION INSTRUCTION Test Circuits Figure1. Standard Test Circuit for Fixed Output Voltage Versions CIN —470 µF, 50V, Aluminum Electrolytic Nichicon “PL Series” COUT —220 µF, 25V Aluminum Electrolytic, Nichicon “PL Series” D1 —5A, 40V Schottky Rectifier, 1N5825 L1 —68 µH, L38 Figure 2. where VREF = 1.23V Standard Test Circuit for Adjustable Output Voltage Versions R VOUT = VREF 1 + R2 1 R2 = R1 VOUT VREF −1 Select R1 to be approximately 1 kW, use a 1% resistor for best stability. CIN —470 µF, 50V, Aluminum Electrolytic Nichicon “PL Series” COUT —220 µF, 35V Aluminum Electrolytic, Nichicon “PL Series” D1 —5A, 40V Schottky Rectifier, 1N5825 L1 —68µH, L38 R1 —1kW, 1% CFF = 1 31 × 103 × R2 6 www.corebai.com CBM2596-XX OPERATION INSTRUCTION Application Information Figure 3. Delayed Startup Figure 4. Undervoltage Lockout for Buck Regulator DELAYED STARTUP The circuit in Figure 3 uses the the ON /OFF pin to provide a time delay between the time the input voltage is applied and the time the output voltage comes up (only the circuitry pertaining to the delayed start up is shown). As the input voltage rises, the charging of capacitor C1 pulls the ON /OFF pin high, keeping the regulator off. Once the input voltage reaches its final value and the capacitor stops charging, and resistor R2 pulls the ON /OFF pin low, thus allowing the circuit to start switching. Resistor R1 is included to limit the maximum voltage applied to the ON /OFF pin (maximum of 25V), reduces power supply noise sensitivity, and also limits the capacitor, C1, discharge current. When high input ripple voltage exists, avoid long delay time, because this ripple can be coupled into the ON /OFF pin and cause problems. This delayed startup feature is useful in situations where the input power source is limited in the amount of current it can deliver. It allows the input voltage to rise to a higher voltage before the regulator starts operating. Buck regulators require less input current at higher input voltages. 7 www.corebai.com CBM2596-XX OPERATION INSTRUCTION UNDERVOLTAGE LOCKOUT Some applications require the regulator to remain off until the input voltage reaches a predetermined voltage. An undervoltage lockout feature applied to a buck regulator is shown in Figure 4, while Figure 5 and 6 applies the same feature to an inverting circuit. The circuit in Figure 5 features a constant threshold voltage for turn on and turn off (zener voltage plus approximately one volt). If hysteresis is needed, the circuit in Figure 6 has a turn ON voltage which is different than the turn OFF voltage. The amount of hysteresis is approximately equal to the value of the output voltage. If zener voltages greater than 25V are used, an additional 47 k resistor is needed from the ON /OFF pin to the ground pin to stay within the 25V maximum limit of the ON /OFF pin. INVERTING REGULATOR The circuit in Figure 7 converts a positive input voltage to a negative output voltage with a common ground. The circuit operates by bootstrapping the regulator’s ground pin to the negative output voltage, then grounding the feedback pin, the regulator senses the inverted output voltage and regulates it. This circuit has an ON/OFF threshold of approximately 13V. Figure 5. Undervoltage Lockout for Inverting Regulator 8 www.corebai.com CBM2596-XX OPERATION INSTRUCTION This example uses the CBM2596-5.0 to generate a −5V output, but other output voltages are possible by selecting other output voltage versions, including the adjustable version. Since this regulator topology can produce an output voltage that is either greater than or less than the input voltage, the maximum output current greatly depends on both the input and output voltage. The curve shown in Figure 8 provides a guide as to the amount of output load current possible for the different input and output voltage conditions. The maximum voltage appearing across the regulator is the absolute sum of the input and output voltage, and this must be limited to a maximum of 40V. For example, when converting +20V to −12V, the regulator would see 32V between the input pin and ground pin. The CBM2596 has a maximum input voltage spec of 40V. Additional diodes are required in this regulator configuration. Diode D1 is used to isolate input voltage ripple or noise from coupling through the CIN capacitor to the output, under light or no load conditions. Also, this diode isolation changes the topology to closley resemble a buck configuration thus providing good closed loop stability. A Schottky diode is recommended for low input voltages, (because of its lower voltage drop) but for higher input voltages, a fast recovery diode could be used. Without diode D3, when the input voltage is first applied, the charging current of CIN can pull the output positive by several volts for a short period of time. Adding D3 prevents the output from going positive by more than a diode voltage. Figure 6. Undervoltage Lockout with Hysteresis for Inverting Regulator This circuit has hysteresis Regulator starts switching at VIN = 13V Regulator stops switching at VIN = 8V 9 www.corebai.com CBM2596-XX OPERATION INSTRUCTION Figure 7. Inverting −5V Regulator with Delayed Startup CIN —68 µF/25V Tant. Sprague 595D 470 µF/50V Elec. Panasonic HFQ COUT —47 µF/20V Tant. Sprague 595D 220 µF/25V Elec. Panasonic HFQ Figure 8. Inverting Regulator Typical Load Current 10 www.corebai.com CBM2596-XX OPERATION INSTRUCTION Because of differences in the operation of the inverting regulator, the standard design procedure is not used to select the inductor value. In the majority of designs, a 33µH, 3.5A inductor is the best choice. Capacitor selection can also be narrowed down to just a few values. Using the values shown in Figure 7will provide good results in the majority of inverting designs. This type of inverting regulator can require relatively large amounts of input current when starting up, even with light loads. Input currents as high as the CBM2596 current limit (approx 4.5A) are needed for at least 2ms or more, until the output reaches its nominal output voltage. The actual time depends on the output voltage and the size of the output capacitor. Input power sources that are current limited or sources that can not deliver these currents without getting loaded down, may not work correctly. Because of the relatively high startup currents required by the inverting topology, the delayed startup feature (C1, R1 and R2) shown in Figure 7 is recommended. By delaying the regulator startup, the input capacitor is allowed to charge up to a higher voltage before the switcher begins operating. A portion of the high input current needed for startup is now supplied by the input capacitor (CIN). For severe start up conditions, the input capacitor can be made much larger than normal. INVERTING REGULATOR SHUTDOWN METHODS To use the ON /OFF pin in a standard buck configuration is simple, pull it below 1.3V (@25℃, referenced to ground) to turn regulator ON, pull it above 1.3V to shut the regulator OFF. With the inverting configuration, some level shifting is required, because the ground pin of the regulator is no longer at ground, but is now setting at the negative output voltage level. Two different shutdown methods for inverting regulators are shown in Figure 9 and Figure 10. Figure 9. Inverting Regulator Ground Referenced Figure 10. Inverting Regulator Ground Referenced Shutdown Shutdown using Opto Device 11 www.corebai.com CBM2596-XX OPERATION INSTRUCTION PACKAGE TO-220-5L Symbol Dimensions In Millimeters Dimensions Inches Min Nom Max Min Nom Max A 4.07 4.45 4.82 0.160 0.175 0.190 b 0.76 0.89 1.02 0.030 0.035 0.040 C 0.36 0.50 0.64 0.014 0.020 0.025 D 14.22 14.86 15.50 0.560 0.585 0.610 E 9.78 10.16 10.54 0.385 0.400 0.415 e 1.57 1.71 1.85 0.062 0.067 0.073 e1 6.68 6.81 6.93 0.263 0.268 0.273 F 1.14 1.27 1.40 0.045 0.050 0.055 H1 5.46 6.16 6.86 0.215 0.243 0.270 J1 2.29 2.74 3.18 0.090 0.108 0.125 L 13.21 13.97 14.73 0.520 0.550 0.580 Øp 3.68 3.81 3.94 0.145 0.150 0.155 Q 2.54 2.73 2.92 0.100 0.107 0.115 12 www.corebai.com CBM2596-XX OPERATION INSTRUCTION TO-263-5L Symbol Dimensions In Millimeters Dimensions Inches Min Nom Max Min Nom Max A 4.07 4.46 4.85 0.160 0.176 0.191 B 0.66 0.84 1.02 0.026 0.033 0.040 C 0.36 0.50 0.64 0.014 0.020 0.025 C2 1.14 1.27 1.40 0.045 0.050 0.055 D 8.65 9.15 9.65 0.341 0.360 0.380 E 9.78 10.16 10.54 0.385 0.400 0.415 e 1.57 1.71 1.85 0.062 0.068 0.073 F 6.60 6.86 7.11 0.260 0.270 0.280 L 14.61 15.24 15.88 0.575 0.600 0.625 L1 2.29 2.54 2.79 0.090 0.100 0.110 L2 - - 2.92 - - 0.115 13 www.corebai.com CBM2596-XX OPERATION INSTRUCTION TO-220-5L (Bent Staggered) Symbol Dimensions In Millimeters Dimensions Inches Min Nom Max Min Nom Max A 4.4 4.6 4.7 0.175 0.180 0.185 b 0.7 0.8 0.9 0.027 0.032 0.037 D 8.4 8.7 8.9 0.330 0.340 0.350 d1 1.0 0.039 d2 6.3 0.248 E 9.91 10.16 10.41 0.390 0.400 0.410 e 1.6 1.7 1.8 0.062 0.067 0.072 F 1.2 1.25 1.3 0.048 0.050 0.052 H1 6.4 H2 20.8 0.850 0.880 J1 2.7 J2 3.9 0.177 0.207 J3 8.4 Q 2.5 0.110 0.120 0.250 21.6 22.4 0.820 0.105 4.5 5.3 0.147 0.331 2.8 3.0 0.100 14 www.corebai.com CBM2596-XX OPERATION INSTRUCTION PACKAGE/ORDERING INFORMATION PRODUCT ORDERING PAKEAGE TRANSPOT MARKING MEDIA,QUANTILY TO-220 2596T-ADJ Tape and Reel,46 -40℃~125℃ TO-263-5 2596DT-ADJ Tape and Reel,500 CBM2596T-3.3 -40℃~125℃ TO-220 2596T-3.3 Tape and Reel,46 CBM2596DT-3.3 -40℃~125℃ TO-263-5 2596DT-3.3 Tape and Reel,500 CBM2596T-5.0 -40℃~125℃ TO-220 2596T-5.0 Tape and Reel,46 CBM2596DT-5.0 -40℃~125℃ TO-263-5 2596DT-5.0 Tape and Reel,500 CBM2596T-12 -40℃~125℃ TO-220 2596T-12 Tape and Reel,46 CBM2596DT-12 -40℃~125℃ TO-263-5 2596DT-12 Tape and Reel,500 TEMPRANGE PACKAGE CBM2596T-ADJ -40℃~125℃ CBM2596DT-ADJ NUMBER CBM2596 CBM2596-3.3 CBM2596-5.0 CBM2596-12 15 www.corebai.com