MCP1602

MCP1602 2.0 MHz, 500 mA Synchronous Buck Regulator with Power-Good Features • • • • • • • • • • • • • • Over 90% Typical Efficiency Output Current: Up To 500 mA Power-Good Output with 262 ms Delay Low Quiescent Current: 45 µA (typical) Low Shutdown Current: 0.05 µA (typical) Automatic PWM to PFM Mode Transition Adjustable Output Voltage: - 0.8V to 4.5V Fixed Output Voltage: - 1.2V, 1.5V, 1.8V, 2.5V, and 3.3V 2.0 MHz Fixed-Frequency PWM (Heavy Load) Internally Compensated Undervoltage Lockout (UVLO) Overtemperture Protection Overcurrent Protection Space Saving Packages: - 8-Lead MSOP - 8-Lead 3x3 DFN General Description The MCP1602 is a high efficient, fully integrated 500 mA synchronous buck regulator with a powergood monitor. The 2.7V to 5.5V input voltage range and low quiescent current (45 µA, typical) makes the MCP1602 ideally suited for applications powered from 1-cell Li-Ion or 2-cell/3-cell NiMH/NiCd batteries. At heavy loads, the MCP1602 operates in the 2.0 MHz fixed frequency PWM mode which provides a low noise, low output ripple, small-size solution. When the load is reduced to light levels, the MCP1602 automatically changes operation to a PFM mode to minimize quiescent current draw from the battery. No intervention is necessary for a smooth transition from one mode to another. These two modes of operation allow the MCP1602 to achieve the highest efficiency over the entire operating current range. The open-drain power-good feature of the MCP1602 monitors the output voltage and provides indication when the output voltage is within 94% (typical) of the regulation value. The typical 2% hystereses in the power-good transition threshold as well as a 262 ms (typical) delay time ensures accurate powergood signaling. The MCP1602 is available in either the 8-pin DFN or MSOP package. It is also available with either an adjustable or fixed output voltage. The available fixed output voltage options are 1.2V, 1.5V, 1.8V, 2.5V, and 3.3V. Additional protection features include: overtemperature, and overcurrent protection. UVLO, Applications • • • • • • • Cellular Telephones Portable Computers Organizers / PDAs USB Powered Devices Digital Cameras Portable Equipment +5V or +3.3V Distributed Systems Package Types MSOP-8 1 SHDN 2 VCC 3 PG PGND 8 LX 7 VIN 6 SHDN VCC PG AGND 1 2 3 4 3x3 DFN-8 8 PGND 7 LX 6 VIN 5 VOUT/VFB 4 AGND VOUT/VFB 5 © 2007 Microchip Technology Inc. DS22061A-page 1 MCP1602 Typical Application Circuit 4.7 µH VIN 2.7V to 4.5V 4.7 µF 6 VIN LX 7 VFB 5 PGND 8 PG 3 RPULLUP 10Ω 2 VCC 4 VOUT 1.5V @ 500 mA 4.7 µF 0.1 µF AGND SHDN 1 MCP1602 ON OFF Processor Reset VIN DS22061A-page 2 © 2007 Microchip Technology Inc. MCP1602 Functional Block Diagram VCC Band Gap Thermal Shutdown TSD IPEAKPWM IPK Limit VREF VIN UVLO UVLO Soft Start SHDN ILIMPWM ILIMPFM Disable Switcher Slope Comp OSC IPEAKPFM -ILPK S R Q Q POFF NOFF LX Switch Drive Logic and Timing PWM/PFM PFM Error Amp PWM/PFM Logic PGND VREF PWM Error Amp EA IPEAKPFM IPEAKPWM -ILPK -IPK Limit VREF VREF VCC PG OV Threshold PG Generator with Delay VFB / VOUT AGND UV Threshold VOUT © 2007 Microchip Technology Inc. DS22061A-page 3 MCP1602 1.0 ELECTRICAL CHARACTERISTICS † Notice: Stresses above 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 those or any other conditions above those indicated in the operational sections of this specification is not intended. Exposure to maximum rating conditions for extended periods may affect device reliability. Absolute Maximum Ratings † VIN - AGND ......................................................................+6.0V All Other I/O .............................. (AGND - 0.3V) to (VIN + 0.3V) LX to PGND ............................................. -0.3V to (VIN + 0.3V) Output Short Circuit Current..................................Continuous Power Dissipation (Note 6) ..........................Internally Limited Storage Temperature.................................... -65oC to +150oC Ambient Temp. with Power Applied................ -40oC to +85oC Operating Junction Temperature.................. -40oC to +125oC ESD Protection On All Pins: HBM..............................................................................3 kV MM...............................................................................200V DC CHARACTERISTICS Electrical Characteristics: Unless otherwise indicated, VIN = 3.6V, COUT = CIN = 4.7 µF, L = 4.7 µH, VOUT(ADJ) = 1.8V, IOUT = 100 mA, TA = +25°C. Boldface specifications apply for the TA range of -40oC to +85oC. Parameters Input Characteristics Input Voltage Maximum Output Current Shutdown Current Quiescent Current SHDN, Logic Input Voltage Low SHDN, Logic Input Voltage High SHDN, Input Leakage Current Undervoltage Lockout Undervoltage Lockout Hysteresis Thermal Shutdown Thermal Shutdown Hysteresis Output Characteristics Adjustable Output Voltage Range Reference Feedback Voltage Feedback Input Bias Current Note 1: 2: 3: 4: VOUT VFB IVFB 0.8 — — — 0.8 -1.5 4.5 — — V V nA Note 2 VIN IOUT IIN_SHDN IQ VIL VIH VL_SHND UVLO UVLOHYS TSHD TSHD-HYS 2.7 500 — — — 45 -1.0 2.40 — — — — — 0.05 45 — — ±0.1 2.55 200 150 10 5.5 — 1 60 15 — 1.0 2.70 — — — V mA µA µA %VIN %VIN µA V mV °C °C Note 5, Note 6 Note 5, Note 6 Note 1 Note 1 SHDN = GND SHDN = VIN, IOUT = 0 mA VIN = 2.7V to 5.5V VIN = 2.7V to 5.5V VIN = 2.7V to 5.5V, SHDN = AGND VIN Falling Sym Min Typ Max Units Conditions Shutdown/UVLO/Thermal Shutdown Characteristics 5: 6: 7: The minimum VIN has to meet two conditions: VIN ≥ 2.7V and VIN ≥ VOUT + 0.5V. Reference Feedback Voltage Tolerance applies to adjustable output voltage setting. VR is the output voltage setting. Regulation is measured at a constant junction temperature using low duty cycle pulse testing. Load regulation is tested over a load range of 0.1 mA to the maximum specified output current. Changes in output voltage due to heating effects are covered by the thermal regulation specification. The maximum allowable power dissipation is a function of ambient temperature, the maximum allowable temperature and the thermal resistance from junction to air (i.e. TA, TJ, θJA). Exceeding the maximum allowable power dissipation causes the device to initiate thermal shutdown. The internal MOSFET switches have an integral diode from the LX pin to the VIN pin, and from the LX pin to the GND pin. In cases where these diodes are forward-biased, the package power dissipation limits must be adhered too. Thermal protection is not able to limit the junction temperature for these cases. The current limit threshold is a cycle-by-cycle current limit. DS22061A-page 4 © 2007 Microchip Technology Inc. MCP1602 DC CHARACTERISTICS (CONTINUED) Electrical Characteristics: Unless otherwise indicated, VIN = 3.6V, COUT = CIN = 4.7 µF, L = 4.7 µH, VOUT(ADJ) = 1.8V, IOUT = 100 mA, TA = +25°C. Boldface specifications apply for the TA range of -40oC to +85oC. Parameters Output Voltage Tolerance Fixed Line Regulation Load Regulation Internal Oscillator Frequency Start Up Time RDSon P-Channel RDSon N-Channel LX Pin Leakage Current Sym VOUT VLINEREG Min -2.5 — — 1.6 — — — -1.0 — 1.0 1.2 — 89 — — — 140 — Typ VR 0.3 0.4 2.0 0.5 450 450 ±0.01 700 — Max +2.5 — — 2.4 — — — 1.0 — 5.5 5.5 96 — — — — 560 0.2 Units % %/V % MHz ms mΩ mΩ µA mA V Note 3 Conditions VIN = VR + 1V to 5.5V, IOUT = 100 mA VIN = VR +1.5V, ILOAD = 100 mA to 500 mA, Note 1 TR = 10% to 90% IP = 100 mA IN = 100 mA SHDN = 0V, VIN = 5.5V, LX = 0V, LX = 5.5V Note 7 TA = 0°C to +70°C TA = -40°C to +85°C VIN ≤ 2.7V, ISINK = 100 µA On Rising VOUT On Falling VOUT VLOADREG FOSC TSS RDSon-P RDSon-N ILX Positive Current Limit Threshold +ILX(MAX) Power-Good (PG) Voltage Range VPG PG Threshold High PG Threshold Low PG Threshold Hysteresis PG Threshold Tempco PG Delay PG Active Time-out Period PG Output Voltage Low VTH_H VTH_L VTH_HYS ΔVTH/ΔT tRPD tRPU PG_VOL 94 92 2 30 165 262 — % of VOUT % of VOUT % of VOUT ppm/°C µs ms V VOUT = (VTH_H + 100 mV) to (VTH_L - 100 mV) VOUT = (VTH_L - 100 mV) to (VTH_H + 100 mV), ISINK = 1.2mA VOUT = VTH_L - 100 mV, IPG = 1.2 mA, VIN > 2.7V IPG = 100 µA, 1.0 < VIN < 2.7V Note 1: 2: 3: 4: 5: 6: 7: The minimum VIN has to meet two conditions: VIN ≥ 2.7V and VIN ≥ VOUT + 0.5V. Reference Feedback Voltage Tolerance applies to adjustable output voltage setting. VR is the output voltage setting. Regulation is measured at a constant junction temperature using low duty cycle pulse testing. Load regulation is tested over a load range of 0.1 mA to the maximum specified output current. Changes in output voltage due to heating effects are covered by the thermal regulation specification. The maximum allowable power dissipation is a function of ambient temperature, the maximum allowable temperature and the thermal resistance from junction to air (i.e. TA, TJ, θJA). Exceeding the maximum allowable power dissipation causes the device to initiate thermal shutdown. The internal MOSFET switches have an integral diode from the LX pin to the VIN pin, and from the LX pin to the GND pin. In cases where these diodes are forward-biased, the package power dissipation limits must be adhered too. Thermal protection is not able to limit the junction temperature for these cases. The current limit threshold is a cycle-by-cycle current limit. © 2007 Microchip Technology Inc. DS22061A-page 5 MCP1602 TEMPERATURE SPECIFICATIONS Electrical Specifications: Unless otherwise indicated, all limits are specified for: VIN + 2.7V to 5.5V Parameters Temperature Ranges Operating Junction Temperature Range Storage Temperature Range Maximum Junction Temperature Package Thermal Resistances Thermal Resistance, 8L-MSOP Thermal Resistance, 8L-3x3 DFN θJA θJA — — 211 60 — — °C/W °C/W Typical 4-layer Board with Internal Ground Plane Typical 4-layer Board with Internal Ground Plane and 2-Vias in Thermal Pad TJ TA TJ -40 -65 — — — — +125 +150 +150 °C °C °C Transient Steady State Sym Min Typ Max Units Conditions DS22061A-page 6 © 2007 Microchip Technology Inc. MCP1602 2.0 Note: TYPICAL PERFORMANCE CURVES The graphs and tables provided following this note are a statistical summary based on a limited number of samples and are provided for informational purposes only. The performance characteristics listed herein are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified operating range (e.g., outside specified power supply range) and therefore outside the warranted range. Note: Unless otherwise indicated, VIN = SHDN = 3.6V, COUT = CIN = 4.7 µF, L = 4.7 µH, VOUT(ADJ) = 1.8V, ILOAD = 100 mA, TA = +25°C. Adjustable or fixed output voltage options can be used to generate the Typical Performance Characteristics. 60 Quiescent Current (µA) 55 VIN = 5.5V 55 Quiescent Current (µA) VOUT = 1.8V TA = +25°C TA = +90°C 50 45 40 35 30 2.7 3.05 3.4 3.75 4.1 4.45 4.8 5.15 5.5 Input Voltage (V) TA = -40°C 50 45 40 35 30 -40 -25 -10 5 20 35 50 65 80 95 110 125 Ambient Temperature (oC) VIN = 4.2V VIN = 3.6V FIGURE 2-1: 100 95 Efficiency (%) 90 85 80 75 70 65 3.0 3.2 IOUT = 300 mA IOUT = 100 mA IQ vs. Ambient Temperature. FIGURE 2-4: 100 IQ vs. Input Voltage. VOUT = 1.2V 90 Efficiency (%) 80 70 60 50 40 30 VIN = 3.6V VIN = 3.0V IOUT = 500 mA VIN = 4.2V VOUT = 1.2V 3.4 3.6 3.8 4.0 4.2 20 0.1 1 Input Voltage (V) 10 100 Output Current (mA) 1000 FIGURE 2-2: (VOUT = 1.2V). 100 Efficiency vs. Input Voltage FIGURE 2-5: (VOUT = 1.2V). 100 Efficiency vs. Output Load VOUT = 1.8V 95 Efficiency (%) 90 85 80 75 70 IOUT = 100 mA 90 Efficiency (%) 80 70 60 50 40 30 20 0.1 VIN = 3.6V VIN = 3.0V IOUT = 300 mA IOUT = 500 mA VIN = 4.2V VOUT = 1.8V 3.0 3.2 3.4 3.6 3.8 4.0 4.2 1 10 100 1000 Input Voltage (V) Output Current (mA) FIGURE 2-3: (VOUT = 1.8V). Efficiency vs. Input Voltage FIGURE 2-6: (VOUT = 1.8V). Efficiency vs. Output Load © 2007 Microchip Technology Inc. DS22061A-page 7 MCP1602 Typical Performance Curves (Continued) Note: Unless otherwise indicated, VIN = SHDN = 3.6V, COUT = CIN = 4.7 µF, L = 4.7 µH, VOUT(ADJ) = 1.8V, ILOAD = 100 mA, TA = +25°C. Adjustable or fixed output voltage options can be used to generate the Typical Performance Characteristics. 100.0 97.5 Efficiency (%) 95.0 92.5 90.0 87.5 85.0 4.2 4.4 4.6 4.8 5.0 5.2 5.4 Input Voltage (V) IOUT = 500 mA IOUT = 100 mA IOUT = 300 mA VOUT = 3.3V 100 90 Efficiency (%) 80 70 60 50 40 30 20 0.1 1 10 100 1000 Output Current (mA) VIN = 5.5V VOUT = 3.3V VIN = 4.2V FIGURE 2-7: (VOUT = 3.3V). 340 PG Active Time-Out (ms) 320 300 280 260 240 220 200 -40 -25 -10 5 Efficiency vs. Input Voltage FIGURE 2-10: (VOUT = 3.3V). 96 PG Threshold (% of V OUT ) 95 94 93 92 91 90 89 88 -40 -25 -10 5 Efficiency vs. Output Load PG Threshold High PG Threshold Low 20 35 50 65 80 95 110 125 20 35 50 65 80 95 110 125 Ambient Temperature (°C) Ambient Temperature (°C) FIGURE 2-8: PG Active Time-out vs. Ambient Temperature. 0.832 Feedback Voltage (V) FIGURE 2-11: PG Threshold Voltage vs. Ambient Temperature. 1.85 Output Voltage (V) 1.84 1.83 1.82 1.81 0 50 100 150 200 250 300 350 400 450 500 Output Current (mA) 0.828 0.824 0.820 0.816 0.812 -40 -25 -10 5 20 35 50 65 80 95 110 125 Ambient Temperature (°C) FIGURE 2-9: Feedback Voltage vs. Ambient Temperature. FIGURE 2-12: Output Voltage vs. Load Current (VOUT = 1.8V). DS22061A-page 8 © 2007 Microchip Technology Inc. MCP1602 Typical Performance Curves (Continued) Note: Unless otherwise indicated, VIN = SHDN = 3.6V, COUT = CIN = 4.7 µF, L = 4.7 µH, VOUT(ADJ) = 1.8V, ILOAD = 100 mA, TA = +25°C. Adjustable or fixed output voltage options can be used to generate the Typical Performance Characteristics. 2.00 Switching Frequency (MHz) 1.98 1.96 1.94 1.92 1.90 -40 -25 -10 5 20 35 50 65 80 95 110 125 Ambient Temperature (°C) 2.10 2.05 2.00 1.95 1.90 1.85 2.70 3.05 3.40 3.75 4.10 4.45 4.80 5.15 5.50 Input Voltage (V) FIGURE 2-13: Switching Frequency vs. Ambient Temperature. 0.6 Switch Resistance (Ω) FIGURE 2-16: Input Voltage. 0.7 Switching Frequency (MHz) Switching Frequency vs. Switch Resistance (Ω) 0.5 P-Channel 0.6 0.5 0.4 N-Channel P-Channel 0.4 N-Channel 0.3 0.2 2.70 3.05 3.40 3.75 4.10 4.45 4.80 5.15 5.50 Input Voltage (V) 0.3 0.2 -40 -25 -10 5 20 35 50 65 80 95 110 125 Ambient Temperature (°C) FIGURE 2-14: Voltage. Switch Resistance vs. Input FIGURE 2-17: Switch Resistance vs. Ambient Temperature. FIGURE 2-15: Waveform. Output Voltage Startup FIGURE 2-18: Waveform. Heavy Load Switching © 2007 Microchip Technology Inc. DS22061A-page 9 MCP1602 Typical Performance Curves (Continued) Note: Unless otherwise indicated, VIN = SHDN = 3.6V, COUT = CIN = 4.7 µF, L = 4.7 µH, VOUT(ADJ) = 1.8V, ILOAD = 100 mA, TA = +25°C. Adjustable or fixed output voltage options can be used to generate the Typical Performance Characteristics. FIGURE 2-19: Waveform. Light Load Switching FIGURE 2-21: Output Voltage Line Step Response vs. Time. FIGURE 2-20: Output Voltage Load Step Response vs. Time. FIGURE 2-22: Power-Good Output Timing. DS22061A-page 10 © 2007 Microchip Technology Inc. MCP1602 3.0 PIN DESCRIPTIONS The descriptions of the pins are listed in Table 3-1. TABLE 3-1: MSOP 1 2 3 4 5 6 7 8 — PIN FUNCTION TABLE DFN 1 2 3 4 5 6 7 8 Exposed Pad Sym SHDN VCC PG AGND VFB/VOUT VIN LX PGND EP Shutdown Input Pin Analog Input Supply Voltage Pin Power Good Output Pin Analog Ground Pin Feedback Voltage (Adjustable Version) / Output Voltage (Fixed Version) Pin Input Supply Voltage Pin Buck Inductor Output Pin Power Ground Pin For the DFN package, the center exposed pad is a thermal path to remove heat from the device. Electrically this pad is at ground potential and should be connected to AGND Description 3.1 Shutdown Control Input Pin (SHDN) 3.6 Power Supply Input Voltage Pin (VIN) The SHDN pin is a logic-level input used to enable or disable the device. A logic high (>45% of VIN) will enable the regulator output. A logic-low (