TD1601SADJ

Techcode® DATASHEET 3A, 150KHz PWM Buck DC/DC Converter TD1601 TD8325 General Description Features The TD1601 is a series of easy to use fixed and adjustable step-down(buck) switch-mode voltage regulators. These devices are available in fixed output voltage of 5V, and an adjustable output version. Both versions are capable of driving a 3A load with excellent line and load regulation.           Requiring a minimum number of external components, these regulators are simple to use and include internal frequency compensation, and a fixed-frequency oscillator. 5V and adjustable output versions Output adjustable from 1.23v to 57V Fixed 150KHz frequency internal oscillator Guaranteed 3A output load current Input voltage range up to 60V TTL shutdown capability Excellent line and load regulation High efficiency Thermal shutdown and current limit protection Available in TO-263 packages The output voltage is guaranteed to ±3% tolerance under specified input voltage and output load conditions. The oscillator frequency is guaranteed to ±15%. External shutdown is included, featuring typically 80 µA standby current. Self protection features include a two stage frequency reducing current limit for the output switch and an over temperature shutdown for complete protection under fault conditions. The TD1601 is available in TO-263-5L packages. Applications Package Types Figure 1. Package Types of TD1601 June 23, 2020.        Techcode Semiconductor Limited 1 Simple High-efficiency step-down regulator On-card switching regulators Positive to negative converter LCD monitor and LCD TV DVD recorder and PDP TV Battery charger Step-down to 3.3V for microprocessors www.techcodesemi.com Techcode® DATASHEET 3A, 150KHz PWM Buck DC/DC Converter TD1601 TD8325 Pin Configurations Figure 2. Pin Configuration of TD1601 (Top View) Pin Description Pin Number Pin Name Description 1 Vin Input supply voltage 2 Output Switching output 3 GND Ground 4 FB Output voltage feedback 5 ON/OFF ON/OFF shutdown. Active is “Low” or floating June 23, 2020. Techcode Semiconductor Limited 2 www.techcodesemi.com Techcode® DATASHEET 3A, 150KHz PWM Buck DC/DC Converter TD1601 TD8325 Ordering Information TD1601 □ □ Circuit Type Output Voltage: 50：5V ADJ: ADJ Package S: TO263-5L Function Block Figure3. June 23, 2020. Function Block Diagram of TD1601 Techcode Semiconductor Limited 3 www.techcodesemi.com Techcode® DATASHEET 3A, 150KHz PWM Buck DC/DC Converter TD1601 TD8325 Absolute Maximum Ratings Note: Stresses greater than those listed under Maximum Ratings may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operation is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability. Parameter Symbol Value Unit Input Voltage VIN -0.3 to 63 V Feedback Pin Voltage VFB -0.3 to 5 V ON/OFF Pin Voltage VEN -0.3 to 5 V Output Pin Voltage VSW -0.3 to Vin+0.3 V Power Dissipation PD Internally limited mW Operating Junction Temperature TJ 150 ℃ Storage Temperature TSTG -65 to 150 ℃ Lead Temperature (Soldering, 10 sec) TLED 260 ℃ ESD (HBM) 2000 V MSL Level3 Thermal Resistance-Junction to Ambient RθJA 23 ℃/W Thermal Resistance-Junction to Case RθJC 3.5 ℃ /W Recommended Operation Conditions (Note3) Parameter Symbol Min. Max. Unit Input Voltage VIN 9 60 V Output voltage Vout 1.23 50 V Converter output current Iout 0 3 A Operating Junction Temperature TJ -40 125 ℃ Operating Ambient Temperature TA -40 85 ℃ June 23, 2020. Techcode Semiconductor Limited 4 www.techcodesemi.com Techcode® DATASHEET 3A, 150KHz PWM Buck DC/DC Converter TD1601 TD8325 Electrical Characteristics VIN =12V, TA =+25℃, unless otherwise noted Parameter Symbol Shutdown Supply Current Condition Min Typ Max Units ON/OFF=5V - 35 - uA Quiescent current IQ ON/OFF=0V;VFB=1.5V - 5 - mA Feedback Voltage VFB 9V≤VIN≤60V 1.200 1.23 1.26 V FOSC1 VFB>0.3 120 150 180 kHz - 350 - mΩ - 4.5 - A - 98 - % Low(Regulator ON) - 0.8 - V VIN Rising - 8.6 - V Input Under Voltage Lockout Threshold Hysteresis - 600 - mV Thermal Shutdown - 150 - ℃ Oscillation Frequency Highside Switch On Resistance Current Limit Maximum Duty Cycle ON/OFF Threshold voltage Input Under Voltage Lockout Threshold June 23, 2020. RDS(ON) IL Peak output current DMAX VIL Techcode Semiconductor Limited 5 www.techcodesemi.com Techcode® DATASHEET 3A, 150KHz PWM Buck DC/DC Converter TD1601 TD8325 Typical Application Circuit Figure 11. Typical Application of TD1601 For 5V Figure 12. Typical Application of TD1601 For ADJ June 23, 2020. Techcode Semiconductor Limited 6 www.techcodesemi.com Techcode® DATASHEET 3A, 150KHz PWM Buck DC/DC Converter TD1601 Function Description The TD1601 regulates input voltages from 9V to 60V down to an output voltage as low as 1.23V, and supplies up to 3A of load current. The TD1601 uses current-mode control to regulate the output voltage. The output voltage is measured at FB through a resistive voltage divider and amplified through the internal trans-conductance error amplifier. The output voltage of the error amplifier is compared to the switch current (measured internally) to control the output voltage. Setting the Output Voltage The output voltage is set using a resistive voltage divider connected from the output voltage to FB. The voltage divider divides the output voltage down to the feedback voltage by the ratio: R V =V ×( ) R +R Thus the output voltage is: V = 1.23 × ( R +R ) R Choose an inductor that will not saturate under the maximum inductor peak current, calculated by: V V L =I + × (1 − ) 2×f ×L V where ILOAD is the load current. The choice of which style inductor to use mainly depends on the price vs. size requirements and any EMI constraints. Input Capacitor The input current to the step-down converter is discontinuous, therefore a capacitor is required to supply the AC current while maintaining the DC input voltage. Use low ESR capacitors for the best performance. Ceramic capacitors are preferred, but tantalum or low-ESR electrolytic capacitors will also suffice. Choose X5R or X7R dielectrics when using ceramic capacitors. Since the input capacitor (C1) absorbs the input switching current, it requires and adequate ripple current rating. The RMS current in the input capacitor can be estimated by: I Inductor The inductor is required to supply constant current to the load while being driven by the switched input voltage. A larger value inductor will result in less ripple current that will in turn result in lower output ripple voltage. However, the larger value inductor will have a larger physical size, higher series resistance, and/or lower saturation current. A good rule for determining inductance is to allow the peak-to-peak ripple current to be approximately 30% or the maximum switch current limit. Also, make sure that the peak inductor current is below the maximum switch current limit. The inductance value can be calculated by: V V L= × (1 − ) f × ∆I V Where VOUT is the output voltage, VIN is the input voltage, fs is the switching frequency, and ∆IL is the peak-to-peak inductor ripple current. June 30, 2020. =I × V V × (1 − V V ) The worst-case condition occurs at VIN=2VOUT, where IC1 = ILOAD/2. For simplification, use an input capacitor with a RMS current rating greater than half of the maximum load current. The input capacitor can be electrolytic, tantalum or ceramic. When using electrolytic or tantalum capacitor, be placed as close to the IC as possible. When using ceramic capacitors, make sure that they have enough capacitance to provide sufficient charge to prevent excessive voltage ripple at input. The input voltage ripple for low ESR capacitors can be estimated by: I V V ∆V = × (1 − ) C ×f V V where C1 is the input capacitance Value. Output Capacitor The output capacitor (C2) is required to maintain the DC Techcode Semiconductor Limited 7 www.techcodesemi.com Techcode® DATASHEET 3A, 150KHz PWM Buck DC/DC Converter output voltage. Ceramic, tantalum, or low ESR electrolytic capacitors are recommended. Under typical application conditions, a minimum ceramic capacitor value of 20µF is recommended on the output. Low ESR capacitors are preferred to keep the output voltage ripple low. The output voltage ripple can be estimated by: ∆VOUT = Vout Vout 1 × 1× R ESR + fs ×L Vin 8×fS ×C2 Where C2 is the output capacitance value and RESR is the equivalent series resistance (ESR) value of the output capacitor. When using ceramic capacitors, the impedance at the switching frequency is dominated by the capacitance which is the main cause for the output voltage ripple. For simplification, the output voltage ripple can be estimated by: V V ∆V = × (1 − ) 8 × f × L × C2 V TD1601 Layout Consideration 1. Input MLCC capacitor is strongly recommended to added and should be connected to the VIN pin and the GND pin as close as possible. 2. Keep sensitive signal traces such as trace connecting FB pin away from the VOUT pins. 3. Make the current trace from SW pin to inductor to the GND as short as possible. 4. Pour a maximized copper area to the GND pin and the VIN pin to help thermal dissipation. When using tantalum or electrolytic capacitors. The ESR dominates the impedance at the switching frequency. For simplification, the output ripple can be approximated to: V V ∆V = × (1 − )×R f ×L V The characteristics of the output capacitor also affect the stability of the regulation system. The TD1601 can be optimized for a wide range of capacitance and ESR values. June 30, 2020. Techcode Semiconductor Limited 8 www.techcodesemi.com Techcode® DATASHEET 3A, 150KHz PWM Buck DC/DC Converter TD1601 Package Information TO263-5L Package Outline Dimensions June 30, 2020. Techcode Semiconductor Limited 9 www.techcodesemi.com Techcode® DATASHEET 3A, 150KHz PWM Buck DC/DC Converter TD1601 Design Notes June 30, 2020. Techcode Semiconductor Limited 10 www.techcodesemi.com