NJU7677 1.8V Operate PWM control Step-Up / Flyback switching regulator IC ■GENERAL DESCRIPTION ■PACKAGE OUTLINE NJU7677 is a high speed low voltage operation switching regulator control IC. It features a totem pole driver that can directly drive an external MOS-FET. Internal soft-start function, dead time control and timer latch function are included, requiring no external components. All parameters can be optimized by additional external components for design flexibility. NJU7677RB1 ■FEATURES ● PWM switching control ● Operating Voltage 1.8V to 7V ● Wide Oscillator Range 300kHz to 1MHz ● Maximum Duty Cycle 90% typ. ● Quiescent Current 600µA typ. ● Soft-Start Function Internal : 4ms typ. or adjustable ● Dead Time Control ● Timer Latch for Short Circuit Protection ● C-MOS Technology ● Package Outline NJU7677RB1 : TVSP8 ■PIN CONFIGURATION 1 8 2 7 3 6 4 5 NJU7677RB1 Ver.2009-09-08 PIN FUNCTION 1. V+ 2. FB 3. IN4. SCP 5. DTC 6. RT 7. GND 8. OUT -1- NJU7677 ■BLOCK DIAGRAM + V FB 0.65V ER⋅AMP IN1V 0.15V Vref Soft Start UVLO Latch PWM Buffer 2µA SCP OUT SCP OSC 2kΩ 0.5V 0.5 1V RT 0.6V A 1V DTC RT GND RT -2- Ver.2009-09-08 NJU7677 ■ABSOLUTE MAXIMUM RATINGS (Ta=25°C) PARAMETER SYMBOL Supply Voltage V+ Output Pin Current IO Power Dissipation PD Operating Temperature Range TOPR Storage Temperature Range TSTG MAXIMUM RATINGS +8 ±50 320 -40 ~ +85 -40 ~ +125 ■RECOMMENDED OPERATING CONDITIONS (Ta=25°C) PARAMETER SYMBOL MIN. Operating Voltage V+ 1.8 Oscillator Timing Resistor RT 30 Oscillation Frequency fOSC 300 TYP. – 47 700 UNIT V mA mW °C °C MAX. 7 120 1,000 UNIT V kΩ kHz ■ELECTRICAL CHARACTERISTICS (V+=3.3V, RT=47kΩ, Ta=25°C) PARAMETER Under Voltage Lockout Block ON Threshold Voltage OFF Threshold Voltage Hysteresis Voltage Soft Start Block Soft Start Time Short Circuit Protection Block Input Threshold Voltage Charge Current Latch Mode ON Threshold Voltage Latch Mode OFF Threshold Voltage Oscillator Block RT Pin Voltage Oscillation Frequency Oscillate Supply Voltage Fluctuations Oscillate Temperature Fluctuations Ver.2009-09-08 SYMBOL VT_ON VT_OFF VHYS TSS TEST CONDITION V+= L → H V+= H → L VT_ON → Duty=80% MIN. TYP. MAX. UNIT 1.6 1.5 60 1.7 1.6 100 1.8 1.7 – V V mV 2 4 8 ms VT_PC ICHG FB Pin VSCP=0V 0.95 1.5 1.00 2 1.05 2.5 V µA VT_LA SCP Pin 0.90 1.00 1.10 V VT_LAOFF SCP Pin 0.35 0.6 0.85 V -8% 630 0.5 700 +8% 770 V kHz VRT fOSC fDV V+=1.8V ~ 7V – 1 – % fDT Ta=-40°C ~ +85°C – 3 – % -3- NJU7677 ■ELECTRICAL CHARACTERISTICS (V+=3.3V, RT=47kΩ, Ta=25°C) PARAMETER Error Amplifier Block Reference Voltage Input Bias Current Open Loop Gain Gain Bandwidth Product Output Source Current Output Sink Current SYMBOL VB IB AV GB IOM+ IOM- TEST CONDITION MIN. TYP. MAX. UNIT -1.0% -0.1 – – 20 1.0 1.00 – 80 1 35 4.0 +1.0% 0.1 – – 50 12 V µA dB MHz µA mA 0.10 0.36 85 45 0.16 0.42 90 55 0.22 0.48 95 65 V V % % IO=-20mA IO=-20mA, V+=1.8V IO=+20mA IO=+20mA, V+=1.8V – – – – 6 10 4.5 8 12 20 9 16 Ω Ω Ω Ω RL=Non Load – 600 900 µA VFB=1V, VIN-=0.9V VFB=1V, VIN-=1.1V PWM Comparate Block Input Threshold Voltage Maximum Duty Cycle Output Block Output High Level ON Resistance Output Low Level ON Resistance General Characteristics Quiescent Current -4- VT_0 VT_50 MAXDUTY_1 MAXDUTY_2 ROH ROH_1.8 ROL ROL_1.8 IDD Duty=0% Duty=50% VFB=0.9V VFB=0.9V, RDTC=43kΩ Ver.2009-09-08 NJU7677 ■ TYPICAL APPLICATIONS Step-Up Converter SBD L V + VOUT CIN R2 NJU7677 C + 1 V OUT 8 2 FB GND 7 3 IN- RT 6 4 SCP DTC 5 CNF COUT FET R1 RT RNF CSCP CS RDTC Flyback Converter V T + SBD VOUT CIN NJU7677 C CNF RNF 1 V 2 + FET OUT 8 FB GND 7 3 IN- RT 6 4 SCP DTC 5 COUT R1 RT CSCP Ver.2009-09-08 R2 RDTC CS -5- NJU7677 ■TYPICAL CHARACTERISTICS Oscillation Frequency vs. Timing Resistance + (V =3.3V, Ta=25 C) 90 AX UTY_1 95 100 10 85 80 100 100 Timing Resistance R (kΩ) OSC o 80 (%) UTY 60 AX 700 680 660 (V+=3.3V, RT=47kΩ, Ta=25 C) 100 T Duty Cycle M D Oscillation Frequency fosc (kHz) o (R =47kΩ, Ta=25 C) 720 0 2 4 6 Operating Voltage V+ (V) 8 40 20 0 0 20 40 60 80 Dead Time Control Resistance R DTC Reference Voltage vs. Operating Voltage T (µA) L 1000 DD 1.005 1 0.995 0.99 (R =47kΩ, R =Non Load, Ta=25 C) 1200 Quiescent Current I B o (Ta=25 C) 1.01 100 (kΩ) Quiescent Current vs. Operating Voltage o Reference Voltage V (V) (kHz) Duty Cycle vs. RDTC Oscillation Frequency vs. Operating Voltage 740 1000 Oscillator Frequency f T -6- o (V =3.3V, Ta=25 C) 100 Maximum Duty Cycle M D (%) 1000 Oscillation Frequency f Maximum Duty Cycle vs. Oscillator Frequency o OSC (kHz) + 0 2 4 6 Operating Voltage V+ (V) 8 800 600 400 200 0 0 2 4 6 Operating Voltage V+ (V) 8 Ver.2009-09-08 NJU7677 ■TYPICAL CHARACTERISTICS Error Amplifier Block Voltage Gain, Phase vs. Frequency (V+=3.3V, Gain=40dB, Ta=25 oC) Output High Level ON Resistance ROH (Ω) 135 Phase Gain 30 90 15 45 0 0.1 20 180 1 10 100 1000 Frequency f (kHz) Output Block Output High Level ON Resistance vs. Temperature (Io=-20mA) 16 Phase Φ (deg) 45 Output Low Level ON Resistance ROL (Ω) Voltage Gain Av (dB) 60 0 10000 Output Block Output Low Level ON Resistance vs. Temperature (Io=+20mA) 14 12 15 V+=1.8V 10 V+=3.3V 5 + V =7V 0 -50 Ver.2009-09-08 -25 0 25 50 75 100 125 Ambient Temperature Ta (oC) V+=1.8V 10 8 6 V+=3.3V 4 2 0 -50 V+=7V -25 0 25 50 75 100 125 Ambient Temperature Ta (oC) -7- NJU7677 ■TYPICAL CHARACTERISTICS Soft Start Time vs. Temperature Reference Voltage vs. Temperature + + 1.005 B 7 (V =3.3V) 1.01 Reference Voltage V (V) Soft Start Time Tss (ms) 8 (V =3.3V) 6 5 4 3 2 -50 1 0.995 0.99 -50 -25 0 25 50 75 100 125 Ambient Temperature Ta (oC) -25 0 25 50 75 100 125 Ambient Temperature Ta (oC) Muximum Duty Cycle vs. Temperature Oscillator Frequency vs. Temperature + 760 Threshold Voltage (V) Muximum Duty Cycle (%) M D 680 660 1.7 MAXDUTY_1 70 V T_ON VT_OFF -25 0 25 50 75 100 125 Ambient Temperature Ta (oC) 60 MAXDUTY_2 50 -25 0 25 50 75 100 125 Ambient Temperature Ta (oC) Quiescent Current vs. Temperature Under Voltage Lockout Block vs. Temperature 1.6 1.5 -50 80 40 -50 -25 0 25 50 75 100 125 Ambient Temperature Ta (oC) 1.65 1.55 90 AX 700 1.75 (V =3.3V) UTY 720 640 -50 100 T 740 1.8 -8- (V =3.3V, R =47kΩ) 1000 Quiescent Current IDD (µA) Oscillator Frequency fOSC (kHz) + (V+=3.3V, R =47kΩ) T 800 600 400 200 0 -50 -25 0 25 50 75 100 125 Ambient Temperature Ta (oC) Ver.2009-09-08 NJU7677 MEMO [CAUTION] The specifications on this databook are only given for information , without any guarantee as regards either mistakes or omissions. The application circuits in this databook are described only to show representative usages of the product and not intended for the guarantee or permission of any right including the industrial rights. Ver.2009-09-08 -9-