NCV3064B

NCP3064, NCP3064B, NCV3064 1.5 A, Step-Up/Down/ Inverting Switching Regulator with ON/OFF Function The NCP3064 Series is a higher frequency upgrade to the popular MC33063A and MC34063A monolithic DC−DC converters. These devices consist of an internal temperature compensated reference, comparator, controlled duty cycle oscillator with an active current limit circuit, driver and high current output switch. This series was specifically designed to be incorporated in Step−Down and Step−Up and Voltage−Inverting applications with a minimum number of external components. The ON/OFF pin provides a low power shutdown mode. Features http://onsemi.com MARKING DIAGRAMS 3064x ALYWG G 1 8 1 SOIC−8 D SUFFIX CASE 751 • • • • • • • • • • • Input Voltage Range from 3.0 V to 40 V Logic Level Shutdown Capability Low Power Standby Mode, Typical 100 mA Output Switch Current to 1.5 A Adjustable Output Voltage Range 150 kHz Frequency Operation Precision 2% Reference Internal Thermal Shutdown Protection Cycle−by−Cycle Current Limiting NCV Prefix for Automotive and Other Applications Requiring Site and Control Changes These are Pb−Free Devices V3064 ALYWG G 1 NCP3064x AWL YYWWG PDIP−8 P, P1 SUFFIX CASE 626 1 NCV3064 AWL YYWWG 8 Applications • Step−Down, Step−Up and Inverting supply applications • High Power LED Lighting • Battery Chargers ON/OFF L1 VOUT 8 1 DFN8 MN SUFFIX CASE 488AF NCP 3064x ALYWG G NCV 3064 ALYWG G ON/OFF Ipk SWC SWE CT VCC CIN VCC FB NCP3064 GND R2 GND Figure 1. Typical Buck Application Circuit © Semiconductor Components Industries, LLC, 2008 November, 2008 − Rev. 4 ÇÇ ÇÇ ÇÇ ÇÇ ÇÇ ÇÇ ÇÇ ÇÇ Ç Ç Ç Ç Ç Ç Ç Ç Rsense R1 D1 CT GND NCP3064 x A L, WL Y, YY W, WW G or G = = = = = = = Specific Device Code B Assembly Location Wafer Lot Year Work Week Pb−Free Package (Note: Microdot may be in either location) ORDERING INFORMATION See detailed ordering and shipping information in the package dimensions section on page 17 of this data sheet. 1 Publication Order Number: NCP3064/D NCP3064, NCP3064B, NCV3064 SOIC−8/PDIP−8 Switch Collector Switch Emitter Timing Capacitor GND 2 3 4 (Top View) 1 8 7 6 5 ON/OFF Ipk Sense VCC Comparator Inverting Input NOTE: DFN8 Switch Emitter Timing Capacitor EP Flag GND (Top View) EP Flag must be tied to GND Pin 4 on PCB Figure 2. Pin Connections Figure 3. Pin Connections 8 ON/OFF ON/OFF TSD 1 Bias R S 7 Ipk Sense Comparator − + 0.2 V 6 VCC Comparator + − 1.25 V Reference Regulator 4 S R 2 Q CT 3 Q Switch Collector Switch Emitter Oscillator Timing Capacitor GND 5 Comparator Inverting Input Figure 4. Block Diagram PIN DESCRIPTION Pin No. 1 2 3 4 5 6 7 8 Pin Name Switch Collector Switch Emitter Timing Capacitor GND Comparator Inverting Input VCC Ipk Sense ON/OFF Internal Darlington switch collector Internal Darlington switch emitter Timing Capacitor Oscillator Input, Timing Capacitor Ground pin for all internal circuits Inverting input pin of internal comparator Voltage supply Peak Current Sense Input to monitor the voltage drop across an external resistor to limit the peak current through the circuit ON/OFF Pin. Pulling this pin to High level turns the device in Operating. To switch into mode with low current consumption this pin has to be in Low level or floating. Description http://onsemi.com 2 Ç Ç Ç Ç ÇÇ ÇÇ ÇÇ ÇÇ Switch Collector ON/OFF Ipk Sense VCC Comparator Inverting Input NCP3064, NCP3064B, NCV3064 MAXIMUM RATINGS (measured vs. Pin 4, unless otherwise noted) RATING VCC (Pin 6) Comparator Inverting Input (Pin 5) Darlington Switch Emitter (Pin 2) (Transistor OFF) Darlington Switch Collector (Pin 1) Darlington Switch Collector to Emitter (Pins 1 and 2) Darlington Switch Peak Current Ipk Sense Voltage (Pin 7) Timing Capacitor Pin Voltage (Pin 3) Moisture Sensitivity Level Lead Temperature Soldering Reflow (SMD Styles Only), Pb−Free Versions ON/OFF Pin Voltage SYMBOL VCC VCII VSWE VSWC VSWCE ISW VIPK VTC MSL TSLD VON/OFF VALUE −0.3 to 42 −0.3 to VCC −0.6 to VCC −0.3 to 42 −0.3 to 42 1.5 −0.3 to (VCC + 0.3 V) −0.2 to +1.4 1 260 (−0.3 to 25) < VCC °C V UNIT V V V V V A V V Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect device reliability. THERMAL CHARACTERISTIC Rating PDIP−8 (Note 5) Thermal Resistance Junction−to−Air SOIC−8 (Note 5) Thermal Resistance Junction−to−Air DFN−8 (Note 5) Storage temperature range Maximum junction temperature Operation Junction Temperature Range (Note 3) NCP3064 NCP3064B, NCV3064 Thermal Resistance Junction−to−Air Thermal Resistance Junction−to−Case Symbol RqJA RqJA RqJA RqJA TSTG TJ MAX TJ Value 100 180 78 14 −65 to +150 +150 0 to +70 −40 to +125 Unit °C/W °C/W °C/W °C °C °C 1. This device series contains ESD protection and exceeds the following tests: Pins 1 through 8: Human Body Model 2000 V per AEC Q100−002; 003 or JESD22/A114; A115 Machine Model Method 200 V 2. This device contains latch−up protection and exceeds 100 mA per JEDEC Standard JESD78. 3. The relation between junction temperature, ambient temperature and Total Power dissipated in IC is TJ = TA + RQ @ PD. 4. The pins which are not defined may not be loaded by external signals. 5. 1 oz copper, 1 in2 copper area. http://onsemi.com 3 NCP3064, NCP3064B, NCV3064 ELECTRICAL CHARACTERISTICS (VCC = 5.0 V, −40°C < TJ < +125°C for NCP3064B and NCV3064, 0°C < TJ < +70°C for NCP3064 unless otherwise specified) Symbol OSCILLATOR fOSC IDISCHG / ICHG IC IDISCH VIPK VSWCE IC(OFF) VTH Frequency Discharge to Charge Current Ratio Capacitor Charging Current Capacitor Discharging Current Current Limit Sense Voltage (VPin 5 = 0 V, CT = 2.2 nF, TJ = 25°C) (Pin 7 to VCC, TJ = 25°C) (Pin 7 to VCC, TJ = 25°C) (Pin 7 to VCC, TJ = 25°C) (TJ = 25°C) 165 110 5.5 150 6.0 275 1.65 200 235 190 6.5 kHz − mA mA mV Characteristic Conditions Min Typ Max Unit OUTPUT SWITCH (Note 6) Darlington Switch Collector to Emitter Voltage Drop Collector Off−State Current (ISW = 1.0 A, TJ = 25°C) (Note 6) (VCE = 40 V) TJ = 25°C NCP3064 NCP3064B, NCV3064 REGLiNE ICII in VIH VIL IIH IIL Threshold Voltage Line Regulation Input Bias Current (VCC = 3.0 V to 40 V) (Vin = Vth) TJ = 25°C TJ = −40°C to +125°C TJ = 25°C TJ = −40°C to +125°C TJ = 25°C TJ = 25°C −1.5 −1.5 −6.0 −1000 2.0 −100 1.0 1.0 1.3 10 V mA COMPARATOR Threshold Voltage 1.25 +1.5 +1.5 6.0 1000 V % % mV nA ON/OFF FEATURE ON/OFF Pin Logic Input Level High VOUT = Nominal Output Voltage ON/OFF Pin Logic Input Level Low VOUT = 0 V ON/OFF Pin Input Current ON/OFF Pin = 5 V (ON) ON/OFF Pin Input Current ON/OFF Pin = 0 V (OFF) 2.2 2.4 − − − − − − 15 1.0 − − 1.0 0.8 V V mA mA TOTAL DEVICE ICC Supply Current (VCC = 5.0 V to 40 V, CT = 2.2 nF, Pin 7 = VCC, VPin 5 > Vth, Pin 2 = GND, remaining pins open) ON/OFF Pin = 0 V (OFF) TJ = 25°C TJ = −40°C to +125°C 85 160 10 7.0 mA ISTBY Standby Quiescent Current 100 100 mA TSHD TSHDHYS Thermal Shutdown Threshold Hysteresis °C °C 6. Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient temperature as possible. 7. The VIPK (Sense) Current Limit Sense Voltage is specified at static conditions. In dynamic operation the sensed current turn−off value depends on comparator response time and di/dt current slope. See the Operating Description section for details. http://onsemi.com 4 NCP3064, NCP3064B, NCV3064 350 OSCILATOR FREQUENCY (kHz) 300 FREQUENCY (kHz) 250 200 150 100 50 0 150 145 140 135 130 125 120 CT = 2.2 nF TJ = 25°C 0 1 2 3 4 5 6 7 8 9 1011 12131415161718192021 CT, CAPACITANCE (nF) 0 5 10 15 20 25 30 35 40 VCC, SUPPLY VOLTAGE (V) Figure 5. Oscilator Frequency vs. Timing Capacitor CT 2.3 2.2 2.1 2.0 1.9 1.8 1.7 1.6 1.5 1.4 1.3 1.2 1.1 1.0 0.9 −40 1.3 1A 0.75 A 0.5 A 1.25 A ICE = 0.25 A VOLTAGE DROP (V) 1.2 1.1 1.0 0.9 0.8 0.7 −20 0 20 40 60 80 100 120 140 0.6 −40 Figure 6. Oscillator Frequency vs. Supply Voltage 0.75 A VOLTAGE DROP (V) 1A 1.25 A 0.5 A ICE = 0.25 A −20 0 20 40 60 80 100 120 140 TJ, JUNCTION TEMPERATURE (°C) TJ, JUNCTION TEMPERATURE (°C) Figure 7. Emitter Follower Configuration Output Darlington Switch Voltage Drop vs. Temperature ON/OFF COMP. THRESHOLD VOLTAGE (V) Figure 8. Common Emmitter Configuration Outp Darlington Switch Voltage Drop vs. Temperatur 1.29 COMP. THRESHOLD VOLTAGE (V) 1.27 1.25 1.23 1.21 1.19 1.6 1.5 1.4 1.3 1.2 1.1 1 −40 −20 0 20 40 60 80 100 120 140 −40 −20 0 20 40 60 80 100 120 140 TJ, JUNCTION TEMPERATURE (°C) TJ, JUNCTION TEMPERATURE (°C) Figure 9. Comparator Threshold Voltage vs. Temperature Figure 10. ON/OFF Comparator Threshold Voltage vs. Temperature http://onsemi.com 5 NCP3064, NCP3064B, NCV3064 0.20 STANDBY SUPPLY CURRENT (mA) −20 0 20 40 60 80 100 120 140 Vipk, CURRENT LIMIT SENSE VOLTAGE (V) 0.19 0.18 0.17 0.16 0.15 −40 450 400 350 300 250 200 150 100 50 0 0 5 10 15 20 25 30 35 40 TJ, JUNCTION TEMPERATURE (°C) VIN, INPUT VOLTAGE (V) Figure 11. Current Limit Sense Voltage vs. Temperature Figure 12. Standby Current vs. Supply Voltage http://onsemi.com 6 NCP3064, NCP3064B, NCV3064 INTRODUCTION The NCP3064 is a monolithic power switching regulator optimized for dc to dc converter applications. The combination of its features enables the system designer to directly implement step−up, step−down, and voltage−inverting converters with a minimum number of external components. Potential applications include cost sensitive consumer products as well as equipment for industrial markets. A representative block diagram is shown in Figure 4. Operating Description capacitor. When the output voltage level reaches nominal, the output switch next cycle turning on is inhibited. The feedback comparator will enable the switching immediately when the load current causes the output voltage to fall below nominal. Under these conditions, output switch conduction can be enabled for a partial oscillator cycle, a partial cycle plus a complete cycle, multiple cycles, or a partial cycle plus multiple cycles. Oscillator The NCP3064 is a hysteric, dc−dc converter that uses a gated oscillator to regulate output voltage. In general, this mode of operation is some what analogous to a capacitor charge pump and does not require dominant pole loop compensation for converter stability. The Typical Operating Waveforms are shown in Figure 13. The output voltage waveform shown is for a step−down converter with the ripple and phasing exaggerated for clarity. During initial converter startup, the feedback comparator senses that the output voltage level is below nominal. This causes the output switch to turn on and off at a frequency and duty cycle controlled by the oscillator, thus pumping up the output filter The oscillator frequency and off−time of the output switch are programmed by the value selected for the timing capacitor CT. Capacitor CT is charged and discharged by a 1 to 6 ratio internal current source and sink, generating a positive going sawtooth waveform at Pin 3. This ratio sets the maximum tON/(tON + tOFF) of the switching converter as 6/(6 + 1) or 0.857 (typical). The oscillator peak and valley voltage difference is 500 mV typically. To calculate the CT capacitor value for the required oscillator frequency, use the equation found in Figure 15. An Excel® based design tool can be found at www.onsemi.com on the NCP3064 product page. Figure 13. Typical Operating Waveform http://onsemi.com 7 NCP3064, NCP3064B, NCV3064 Peak Current Sense Comparator With a voltage ripple gated converter operating under normal conditions, output switch conduction is initiated by the Voltage Feedback comparator and terminated by the oscillator. Abnormal operating conditions occur when the converter output is overloaded or when feedback voltage sensing is lost. Under these conditions, the Ipk Current Sense comparator will protect the Darlington output Switch. The switch current is converted to a voltage by inserting a fractional W resistor, RSC, in series with VCC and the Darlington output switch. The voltage drop across RSC is monitored by the Current Sense comparator. If the voltage drop exceeds 200 mV with respect to VCC, the comparator will set the latch and terminate output switch conduction on a cycle−by−cycle basis. This Comparator/Latch configuration ensures that the Output Switch has only a single on−time during a given oscillator cycle. Real Vturn−off on Rs Resistor I1 di/dt slope Io t_delay I through the Darlington Switch inductor pins and with decreasing inductor value. It is recommended to check the real max peak current in the application at worst conditions to be sure that the maximum peak current will never get over the 1.5 A Darlington Switch Current maximum rating. Thermal Shutdown Internal thermal shutdown circuitry is provided to protect the IC in the event that the maximum junction temperature is exceeded. When activated, typically at 160°C, the Output Switch is disabled. The temperature sensing circuit is designed with 10°C hysteresis. The Switch is enabled again when the chip temperature decreases to at least 150°C threshold. This feature is provided to prevent catastrophic failures from accidental device overheating. It is not intended to be used as a replacement for proper heat−sinking. Output Switch Vipk(sense) The output switch is designed in a Darlington configuration. This allows the application designer to operate at all conditions at high switching speed and low voltage drop. The Darlington Output Switch is designed to switch a maximum of 40 V collector to emitter voltage and current up to 1.5 A ON/OFF Function Figure 14. Current Sense Waveform The VIPK(Sense) Current Limit Sense Voltage threshold is specified at static conditions. In dynamic operation the sensed current turn−off value depends on comparator response time and di/dt current slope. Real Vturn−off on Rsc resistor Vturn_off = Vipk(sense) + Rs*(tdelay*di/dt) Typical Ipk comparator response time tdelay is 350 ns. The di/dt current slope is growing with voltage difference on the The ON/OFF function disables switching and puts the part into a low power consumption mode. A PWM signal up to 1 kHz can be used to pulse the ON/OFF and control the output. Pulling this pin below the threshold voltage (~1.4 V) or leaving it open turns the regulator off and has a standby current