GM7109 150KHz, 2A STEP DOWN VOLTAGE SWITCHING REGULATORS Description Features GM7109 series is designed to provide all the active function for a step-down (buck) switching regulator, and drives a maximum load current as high as 2A line and load regulations. GM7109 is available in fixed output voltages of 3.3V, 5V, and a versatile Adjustable output version. These regulators are simple to use and require minimum number of external components. The features include internal frequency compensation and a fixed-frequency oscillator. The GM7109 is high-efficiency replacements for popular three-terminal linear regulators, and is requiring a smaller heat sink or even no need heat sink. GM7109 performs well with standard inductors from most of manufacturers, and simplifying the design of switch-mode power supplies. External shutdown is included with 80 µA (typical) standby current. The output switch has cycle-by-cycle current limiting as well as thermal shutdown for full protection under fault conditions. Standard SOP8 & PSOP8 package 3.3V, 5V, and Adjustable output versions Adjustable version output voltage range 1.23V to 37V VOUT accuracy is to ±2% under specified input voltage the output load conditions Input voltage range up to 40V Requires only 4 external components with High efficiency TTL shutdown capability, low power standby mode Built-in thermal shutdown, current limit protection Uses standard inductors 150 kHz fixed frequency internal oscillator GM7109 operates at a switching frequency of 150 kHz which allowing smaller size filter components than what would be needed with lower frequency switching regulators. GM7109 series are available in a standard 8-lead SO package or 8 lead SO package with heat sink. Application Pre-regulator for linear regulators On-card/board switching regulators High-efficiency step-down buck regulator Positive to negative converter (buck-boost) LCD Monitors Typical Application Circuits FB 3 1 VIN Output 2 CIN 680µF SD 4 L1 68µH GND 5, 6, 7, 8 D1 1N5824 5V regulated output, COUT 220µF www.gammamicro.com.tw GM7109V1.00 GM7109-5.0 1 Unregulated DC Input 1 GM7109 150KHz, 2A STEP DOWN VOLTAGE SWITCHING REGULATORS Marking Information and Pin Configurations (Top View) SO8 & PSO8 GND GND GND GND GM7109 VVVAYWW VIN VOUT SD FB VVV: 033=3.3V, 050=5.0V, 00A=ADJ A: Assembly / Testing factory code Y: Year WW: Week Ordering Information GM7109V1.00 Ordering Number 2 Output Voltage Package Shipping GM7109-AS8T Adj SOP8 100 Units / Tube GM7109-AS8R Adj SOP8 2500 Units / Reel GM7109-APS8T Adj PSOP8 100 Units / Tube GM7109-APS8R Adj PSOP8 2500 Units / Reel GM7109-3.3S8T 3.3 SOP8 100 Units / Tube GM7109-3.3S8R 3.3 SOP8 2500 Units / Reel GM7109-3.3PS8T 3.3 PSOP8 100 Units / Tube GM7109-3.3PS8R 3.3 PSOP8 2500 Units / Reel GM7109-5.0S8T 5.0 SOP8 100 Units / Tube GM7109-5.0S8R 5.0 SOP8 2500 Units / Reel GM7109-5.0PS8T 5.0 PSOP8 100 Units / Tube GM7109-5.0PS8R 5.0 PSOP8 2500 Units / Reel GM7109 150KHz, 2A STEP DOWN VOLTAGE SWITCHING REGULATORS Absolute Maximum Ratings (Note 1) Rating Value Unit 45 V SD Pin Input Voltage / Feed Back Pin Voltage -0.3 + VIN + 0.3 V Output Voltage to Ground (Steady State) -0.3 + VIN + 0.3 V Internally Limited - 36 ℃/W - 65 to 150 ℃ + 150 ℃ Operating Temperature Range - 40 to 125 ℃ Minimum EDS Rating (Note 2) 2 kV + 260 ℃ Maximum Supply Voltage Power Dissipation Thermal Resistance – Junction to Ambient (θJA) ** 2 square inch of FR-4, double sided, 1oz. minimum copper weight, is recommended Storage Temperature Range Maximum Junction Temperature Lead Temperature (Soldering, 10 sec) Block Diagram SD VIN Current Source Bias 1.235V Reference 2.5V Reference Start UP 220 COMP Current Limit 2.5V COMP GM R2 220mV 2A Switch AMP COMP Latch Driver R1 = 2.5K Reset Freq. Shift 150KHz OSC Thermal Limit OUTPUT GND GM7109V1.00 For 3.3V, R2 = 4.2K For 5.0V, R2 = 7.6K For Adj, R2 = 0 and R1 = OPEN 3 GM7109 150KHz, 2A STEP DOWN VOLTAGE SWITCHING REGULATORS Electrical Characteristics: GM7109-ADJ (Specifications with standard type face are for T = 25℃, and those with bold face type apply over full Operating Temperature rage) Parameter Condition Output Voltage 4.5V < VIN < 40V, 0.2A < ILOAD < 2A Efficiency VIN =12V, ILOAD=2.0A, VOUT = 3V Symbol VOUT Min 1.193 1.180 η Typ 1.230 Max Unit 1.267 V 1.280 88 % Electrical Characteristics: GM7109-3.3 (Specifications with standard type face are for T = 25℃, and those with bold face type apply over full Operating Temperature rage) Parameter Condition Output Voltage 4.75V < VIN < 40V, 0.2A < ILOAD < 2A Efficiency VIN =12V, ILOAD=2.0A Symbol VOUT Min 3.168 3.135 η Typ 3.300 Max Unit 3.432 V 3.465 73 % Electrical Characteristics: GM7109-5.0 GM7109V1.00 (Specifications with standard type face are for T = 25℃, and those with bold face type apply over full Operating Temperature rage) 4 Parameter Condition Output Voltage 7V < VIN < 40V, 0.2A < ILOAD < 2A Efficiency VIN =12V, ILOAD=2.0A Symbol VOUT η Min 4.800 4.7500 Typ 5.000 80 Max 5.200 5.250 Unit V % GM7109 150KHz, 2A STEP DOWN VOLTAGE SWITCHING REGULATORS Electrical Characteristics: All Output Voltage Versions (Specifications with standard type face are for TJ = 25℃, and those with bold face type apply over full Operating Temperature rage. Unless otherwise specified, VIN = 12V) Parameter Condition Symbol Min Typ Feedback Bias Current VFB =1.3V (Adjustable Version Only) Ib - 10 Oscillator Frequency (Note 6) fo Saturation Voltage IOUT = 2A (Notes 7, 8) Max Duty Cycle (ON) (Note 8) DC 100 Min Duty Cycle (OFF) (Note 9) DC 0 Current Limit Peak Current (Notes 7, 8) lCL Output Leakage Current Output =0V (Notes 7, 9, 10) 50 Unit nA 100 127 150 110 VSAT Max - 173 kHz 173 1.16 1.4 V 1.5 Output = -0.9V (Note 10) Quiescent Current (Note 9) Standby Quiescent Current SD Pin = 5V (OFF), Note 10 - % % 3.4 A - - 100 µA - 2 - mA lQ - 5 - mA lSTBY - 70 200 µA lL SD Pin Logic lnput Level Low (ON) VIH - 1.3 0.6 High (OFF) VIL 2.0 1.3 - SD Pin lnput Current VLOGlC = 2.5V (OFF) IH 5 15 µA VLOGlC = 0.5V (ON) IL 0.02 5 µA V Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. Note 2: The human body model is a 100pF capacitor discharged through a 1.5KΩresistor into each pin. Note 3: Typical numbers are at 25°C and represent the most likely norm. Note 5: External components such as the catch diode, inductor, input and output capacitors, and voltage programming resistors can affect switching regulator system performance. When the GM7109 is used as shown in the Figure 1 test circuit, system performance will be as shown in system parameters section of Electrical Characteristics. Note 6: The switching frequency is reduced when the second stage current limit is activated. Note 7: No diode, inductor or capacitor connected to output pin. Note 8: Feedback pin removed from output and connected to 0V to force the output transistor switch ON. Note 9: Feedback pin removed from output and connected to 12V for the 3.3V, 5V, and the ADJ. version. GM7109V1.00 Note 4: All limits guaranteed at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits are 100% production tested. All limits at temperature extremes are guaranteed via correlation using standard Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level (AOQL). 5 GM7109 150KHz, 2A STEP DOWN VOLTAGE SWITCHING REGULATORS Test Circuit and Layout Guidelines Careful layout is important with any switching regulators. Rapidly switching currents associated with wiring inductance generate voltage transients which can cause problems. To minimize inductance and ground loops, the lengths of the leads indicated by heavy lines in Figure 1&2 below should be kept as short as possible. Single point grounding (as indicated or ground plane construction should be used for best results. When using the Adjustable version, place the programming resistors as close as possible to GM7109, to keep the sensitive feedback wiring short. 3 FB 1 VIN VIN Unregulatedd DC Input L1 100µH GM7109-x.x 5~8 GND CIN 100µF 4 SD 2 VOUT VOUT D1 L O A D COUT 680µF Figure 1 Fixed Ouput Votlage Versions CIN = 470µF, Aluminum Electrolytic COUT = 220µF, 25V, Aluminum Electrolytic D1 = Schottky, 5A/40V L1 = 68µH 1 3 FB GM7109-A VIN GM7109V1.00 VIN Unregulatedd DC Input 6 CIN 100µF 5~8 GND 4 SD L1 100µH VOUT 2 VOUT R2 D1 COUT 680µF Figure 2 Adjustable Ouput Votlage Versions CIN = 470µF, Aluminum Electrolytic COUT = 220µF, 25V, Aluminum Electrolytic D1 = Schottky, 5A/40V L1 = 68µH VOUT = VREF (1 + R2/R1) R1 L O A D GM7109 150KHz, 2A STEP DOWN VOLTAGE SWITCHING REGULATORS Typical Performance Characteristics Figure 3. Switch Saturation Voltage 1.4 SWlTCH CURRENT LlMlT (A) 1.2 1.1 TJ = - 40°C 1.0 0.9 0.8 25° 125 °C C 2 1 0 3 VlN = 12V VOUT =5V 5.0 4.5 4.0 3.5 -50 4 ILOAD = 2A 1.0 ILOAD = 1A 0.8 16 SUPPLY VOLTAGE (V) CURRENT (µA) TJ = -40°C and 125°C 40 20 Switch OFF 4 4 3 2 1 VOUT = 1.23V ILOAD = 120mA Figure 10. Switching Frequency 8 160 VIN = 40V TJ = -40°C and 125°C 7 155 FREQUENCY (kHz) 6 CURRENT(µA) 8 0 -50 -25 0 25 50 75 100 125 JUNCTION TEMPERATURE (°C) 40 Figure 9. SD Pin Current (Sinking) 5 4 3 2 150 145 140 135 130 1 0 Switch ON 5 TJ = 25°C 10 20 30 SUPPLY VOLTAGE (V) 125 Figure 8. Minimum Operating Supply Voltage VON/OFF = 5V 0 0 100 12 150 60 75 0 -50 -25 0 25 50 75 100 125 JUNCTION TEMPERATURE (°C) Figure 7. Shutdown Quiescent Current 80 50 4.5V < VIN < 40V ISWITCH = 0 20 0.6 -50 -25 0 25 50 75 100 JUNCTION TEMPERATURE (°C) 100 25 24 SWlTCH CURRENT (mA) INPUT - OUTPUT DIFFERENTIAL L = 33µH RIND = 0.04 VOUT = VREG = 50mV 1.2 0 Figure 6. Operating Quiescent Current Figure 5. Dropout Voltage 1.6 1.4 -25 JUNCTlON TEMPERATURE (°C) SWlTCH CURRENT (A) 0 5 10 15 20 SD PlN VOLTAGE(V) 25 120 -50 -25 0 25 50 75 100 125 JUNCTION TEMPERATURE (°C) GM7109V1.00 SATURATlON VOLTAGE (V) 5.5 VlN =12V 1.3 0.7 0.6 Figure 4. Switch Current Limit 7 GM7109 150KHz, 2A STEP DOWN VOLTAGE SWITCHING REGULATORS Package Outline Dimensions – SO 8 0.189 - 0.197 (4.800 - 5.004) 0.228 - 0.244 (5.791 - 6.198) 0.016 - 0.050 (0.406 - 0.270) D 0.014 - 0.020 (0.356 - 0.508) 0.050 (1.270) TYP 0.150 - 0.157 (3.810 - 3.988) 0.053 - 0.059 (1.346 - 1.753) SEATING PLAN 0.004 - 0.010 (0.012 - 0.254) 0.008 - 0.010 (0.203 - 0.254) 8.0 MAX Package Outline Dimensions – PSO 8 0.189 - 0.197 (4.800 - 5.004) 0.090 (2.286) 0.095 - 0.130 0.228 - 0.244 (2.410 - 3.300) (5.791 - 6.198) 0.016 - 0.050 (0.406 - 0.270) D 0.014 - 0.020 (0.356 - 0.508) 0.050 (1.270) TYP 0.150 - 0.157 (3.810 - 3.988) 0.053 - 0.059 (1.346 - 1.753) GM7109V1.00 SEATING PLAN 8 0.004 - 0.010 (0.012 - 0.254) 0.008 - 0.010 (0.203 - 0.254) 8.0 MAX GM7109 150KHz, 2A STEP DOWN VOLTAGE SWITCHING REGULATORS Ordering Number GM 7109 A APM Gamma R Output Voltage Package Type Shipping Type A: Adj 3.3 = 3.3V 5.0 =5.0V S8: SO 8 PS8: Power SO 8 R: Taping & Reel T: Tube GM7109V1.00 Micro Circuit Type S8 8 10 6 9