AME. Low Dropout 3A CMOS Regulator AME8846. n General Description. n Typical Application. n Features. n Functional Block Diagram.

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1 8846 n General Description n Typical Application The 8846A/B family of positive CMOS linear regulators provides ultra low-dropout voltage and low quiescent current (typically 600uA), thus making them ideal for power-saving system. These rugged devices have both Thermal Shutdown and Current limit to prevent device failure under the "Worst" of operating conditions. The 8846A/B also provides SS time in order to reduce inrush current in different applications. V IN 10µF Chip Enable IN OUT 8846 ADJ EN VCNTL PG GND 1µF = 0.8 x R1+R2 R2 R1 10µF R2 100K n Features l Low Dropout Voltage: 25 o C l Adjustable Output Voltage (0.8V to 3.3V) l High Output Accuracy +1.5% l Support Low ESR Multi-layer ceramic capacitors (MLCC) Application l Power Good Output l Fast Transient Response l Soft-Start Function l Over-Temperature Shutdown with Hysteresis l Current Limiting and Short Current Limit Protection l Green Products Meet RoHS Standards n Applications l Motherboard Application l Notebook Application l Front Side Bus VTT(1.2V/3A) n Functional Block Diagram IN EN VCNTL OCP OTP POR Driver 0.8V 0.72V Error Amplifier OUT ADJ PG GND 1

2 8846 n Pin Configuration 8 SOP-8/PP Top View x-xxxADJ 1. PG 2. EN 3. IN 4. VCNTL 5. NC 6. OUT 7. ADJ 8. GND Note: Connect exposed pad (heat sink on the back) to GND. DFN-10B (3mmx3mmx0.75mm) Top View x-xxxADJ 1. OUT 2. OUT 3. OUT 4. ADJ 5. PG 6. EN 7. IN 8. IN 9. IN 10. VCNTL n Pin Configuration Pin Number SOP-8/PP DFN-10B Pin Name Pin Description 1 5 PG Power Good Open Drain Output. 2 6 EN Enable Input (Active-High). 3 7, 8, 9 IN Input Voltage VCNTL Control Input Voltage. 5 N/A NC No Internal Connection. 6 1, 2, 3 OUT Output Voltage. 7 4 ADJ Set the outpot voltage by the external feedback resistors. ( R1 + R2) = 0.8V R GND Ground. 2

3 8846 n Ordering Information 8846x - x x x xxx Output Voltage Number of Pins Package Type Pin Configuration Enable Pin Function Enable Pin Function Pin Configuration Package Type Number of Pins Output Voltage A: Internal Pull High A 1. PG V: DFN A: 8 ADJ: Adjustable B: Internal Pull Low (SOP-8/PP) 2. EN Z: SOP/PP B: IN 4. VCNTL 5. NC 6. OUT 7. ADJ 8. GND A (DFN-10B) 1. OUT 2. OUT 3. OUT 4. ADJ 5. PG 6. EN 7. IN 8. IN 9. IN 10. VCNTL 3

4 8846 n Absolute Maximum Ratings Parameter Maximum Unit Control Input Voltage, 3 to 6 Power Input Voltage, V IN 1 to 6 Output Voltage, GND-0.3 to V IN +0.3 V Other Pins -0.3 to +0.3 Electrostatic Discharge (HBM) 1500 V Electrostatic Discharge (MM) 200 Electrostatic Discharge (CDM) 1000 Junction Temperature 150 Storage Temperature Range -65 to +150 V o C n Recommended Operating Conditions Parameter Symbol Rating Unit Power Input Voltage V IN 1 to 5.5 V Control Input Voltage 3V to 5.5 V Ambient Temperature Range T A - 40 to +85 o C Junction Temperature Range T J - 40 to +125 o C 4

5 8846 n Thermal Information Parameter Package Die Attach Symbol Maximum Unit Thermal Resistance (Junction to Case) Thermal Resistance (Junction to Ambient) Power Dissipation SOP-8/PP 19 θ JC DFN-10B 8.5 SOP-8/PP 84 Conductive Epoxy θ JA DFN-10B 65 SOP-8/PP 1450 P D DFN-10B 1540 o C / W mw Lead Temperature (Soldering 10 Sec)** 260 o C * Measure θ JC on backside center of Exposed Pad. ** MIL-STD-202G210F 5

6 8846 n Electrical Specifications V IN =(NOM) +0.5V, =V EN =5V, I OUT =1mA, and C OUT =10µF, C IN =10µF, unless otherwise noted. Typical values are at T A =25 o C. Parameter Symbol Test Condition Min Typ Max Units Supply Input Voltage Power Input Voltage Range Control Input Voltage Range POR Threshold POR Hysteresis V IN V Quiescent Current =5.5V ma Feedback Voltage Reference Voltage Dual Power Output Voltage Range V ADJ =5V, V IN =3.3V 0.8 V IN -V DROP V Power Input Line Regulation V LINE_IN 1.2V<V IN <4.5V =V EN =5V %/V I OUT =0A, =V ADJ Load Regulation V LOAD I OUT =0A~3A %A Dropout Voltage V DROP I OUT =2A, =V EN =5.0V =V ADJ I OUT =3A, =V EN =5.0V =V ADJ mv Discharge R DS(ON) EN=Low 150 Ω Enable EN Pin Voltage High EN Pin Voltage Low EN Input Current Control Input Current in Shutdown V ENH 1.4 V ENL 0.8 I EN =V EN =5V A I SHDN V EN =0V B I SHDN V EN =0V V µa Soft Start Time ms 6

7 8846 n Electrical Specifications (Contd.) Parameter Symbol Test Condition Min Typ Max Units Power Good and Delay PG Threshold Voltage for Power Good PG Threshold Voltage for Power Not Good V FB Rising 90 V FB Falling 80 % PG Low Voltage PG Delay Time PG sinks 5mA V ms Protection Function Current Limit Short Circuit Current Thermal Shutdown Temperature Thermal Shutdown Hysteresis I LIM <0.3V T SD 160 T SD 30 A o C Note 1. Quiescent Current is defined by I Q =I IN -I OUT (I OUT =0mA) 7

8 8846 n Detailed Description The 8846A/B family of positive CMOS linear regulators provides ultra low-dropout voltage, high output current with low ground current, very low input voltage and very low dropout voltage at up to 3A. It operates with a VIN as low as 1V and VCNTL voltage 3V with output voltage programmable as low as 0.8V. Enable The 8846A/B has a dedicated enable pin, when this pin is in the logic low condition, the MOS pass transistor shuts off, and all internal circuits are powered down. For 8846A, the EN pin is pulled up by an internal resistor to enable normal operation. So the regulator will be turn on when EN pin is floating. It is not necessary to use an external pull up resistor to save cost. For 8846B, the EN pin is pulled low by an internal resistor to enable normal operation. So the regulator will be turn off when EN pin is floating. It is not necessary to use an external pull low resistor to save cost. Short Circuit Current-Limit The short circuit current-limit function reduces the current-limit level down to 1.5A (typical) when short circuit conditions. Thermal Shutdown A thermal shutdown circuit limits the junction temperature of 8846A/B. When the junction temperature exceeds 160 o C, the over-temperature protection circuit turns off the pass transistor allowing the device to cool down, The pass transistor turns on again after the junction temperature cools by 30 o C. Power Good and Delay The power good function is an open-drain output. Connects a 100kΩ pull up resistor to VOUT to obtain an output voltage. The PG pin will go high 3mS (typ) after the output voltage arrives at 90% of normal output voltage. Soft-Start The 8846A/B features a soft start function that limits inrush current. The soft start time is typically 1.4ms. Current-Limit The 8846A/B contains an independent current limit and short circuit current protection to prevent damage during fault conditions. The current limit monitors and controls the pass transistor's gate voltage, limiting the output current to higher than 4.5A typical. 8

9 8846 n Application Information Input Capacitor The input capacitance is at least 10µF located as close as possible to the IC is recommended. Output Capacitor The 8846A/B is stable with an output capacitor to ground of 10uF or greater. The output capacitor selection is dependent on ESR (equivalent series resistance) and capacitance of the output capacitor over the desired operating temperature. The Ultra-low-ESR capacitors (such as ceramic chip capacitors) and low-esr bulk capacitors (such as solid tantalum, POSCap, and Aluminum electrolytic capacitors) can all be used as output capacitors. For applications with large load current transitions, low-esr bulk capacitors are normally recommended. Decoupling ceramic capacitors must be placed as close as possible to the load and ground pins. The impedance of the layout must be minimized. Power Dissipation The power dissipation is defined as P D =(V IN - ) x I OUT + V IN x I Q The maximum power dissipation depends on the thermal resistance of IC package, PCB material & PCB design (The copper area of pad), the rate of surrounding airflow and temperature difference between junction and ambient. The maximum power dissipation can be calculated by the following formula: P D( MAX ) = ( T T ) J θ JA A Note: Operation junction temperature not exceed 125 o C Setting Output Voltage The output voltage is programmed by the resistor divider connected to the FB pin. The output voltage is given by the following equation: ( R1 R2) + = 0.8V R2 The feedback resistor of resistance value support > 100K ohm and no require forward capacitor. 9

10 8846 n Characterization Curve Load Transient Response Load Transient Response =5V, V IN =1.8V, =1.2V =5V, V IN =1.8V, =1.2V (20mV/Div) (20mV/Div) I OUT I OUT (1A/Div) (1A/Div) Time (2ms/Div) Time (2ms/Div) V IN Line Transient Response V IN Line Transient Response =5V, =1.2V,I OUT =0A =5V, =1.2V,I OUT =2A V IN V IN (20mV/Div) (20mV/Div) Time(500µs/Div) Time(500µs/Div) Line Transient Response Line Transient Response V IN=1.8V, =1.2V, I OUT=0A V IN =1.8V, =1.2V, I OUT =2A (20mV/Div) (20mV/Div) Time(2ms/Div) Time(2ms/Div) 10

Time (1ms/Div) Time (2ms/Div) Start Up form V IN Short Circuit Protection I OUT=3A =5V, V IN =1.8V, =1.

0 0.5 Over Current Protection =5V,V IN =3.

11 8846 n Characterization Curve (Contd.) Start Up form Enable Start Up form EN (5V/Div) I OUT=3A (5V/Div) I OUT =3A PG PG I IN I IN (2A/Div) (2A/Div) Time (1ms/Div) Time (2ms/Div) Start Up form V IN Short Circuit Protection I OUT=3A =5V, V IN =1.8V, =1.2V V IN PG I IN (2A/Div) I OUT (1A/Div) Time (2ms/Div) Time(100µs/Div) Output Votlage (V) Over Current Protection =5V,V IN =3.3V Dropout Voltage (mv) Dropout Voltage vs Load Current & Temperature =5V,=1.2V 125 o C 25 o C -40 o C Load Current I OUT (A) Load Current I OUT (A) 11

12 8846 n Characterization Curve (Contd.) Short Circuit Current vs. Temperature Output Voltage vs. Temperature Short Circuit Current (A) =5V, V IN=1.8V, =1.2V Output Voltage (V) =5V, V IN =1.8V, =1.2V Temperature ( o C) Temperature ( o C) Quiescent Current vs. Temperature POR Threshold Voltage vs. Temperature Quiescent Current (ma) =5V, V IN =1.8V, =1.2V POR Voltage (V) V IN=1.8V, =1.2V Rising Falling Temperature ( o C) Temperature ( o C) Standby Current vs. Temperature 12 Standby Current (µa) =5V, V IN =1.8V, =1.2V 8846A 8846B Temperature ( o C)

13 8846 n Tape and Reel Dimension SOP-8/PP P PIN 1 W Carrier Tape, Number of Components Per Reel and Reel Size DFN-10B (3mmx3mmx0.75mm) P PIN 1 W Carrier Tape, Number of Components Per Reel and Reel Size Package Carrier Width (W) Pitch (P) Part Per Full Reel Reel Size DFN-10B (3x3x0.75m m ) 12.0±0.1 m m 4.0±0.1 m m 3000pcs 330±1 m m 13

14 8846 n Package Dimension SOP-8/PP TOP VIEW D1 SIDE VIEW SYMBOLS MILLIMETERS INCHES MIN MAX MIN MAX A E2 E E1 L1 A A C PIN 1 D C E E L b D b e A2 A e BSC BSC θ 0 o 8 o 0 o 8 o FRONT VIEW A1 E D

15 8846 n Package Dimension DFN-10B (3mmx3mmx0.75mm) TOP VIEW D BOTTOM VIEW e L E E1 PIN 1 IDENTIFICATION b D1 A G1 G REAR VIEW SYMBOLS MILLIMETERS INCHES MIN MAX MIN MAX A D E e D E b L G G

16 Life Support Policy: These products of, Inc. are not authorized for use as critical components in life-support devices or systems, without the express written approval of the president of, Inc., Inc. reserves the right to make changes in the circuitry and specifications of its devices and advises its customers to obtain the latest version of relevant information., Inc., July 2013 Document: A001A-DS8846-A.03 Corporate Headquarter, Inc. 8F, 12, WenHu St., Nei-Hu Taipei 114, Taiwan. Tel: Fax:

AME. Low Dropout 2A CMOS Regulator AME8882. n General Description. n Typical Application. n Features. n Functional Block Diagram.

AME. Low Dropout 2A CMOS Regulator AME8882. n General Description. n Typical Application. n Features. n Functional Block Diagram. 8882 n General Description n Typical Application The 8882A/B family of positive CMOS linear regulators provides ultra low-dropout voltage (240mV @2A) and low quiescent current (typically 600uA), thus making