Advanced Monolithic Systems
FEATURES
• Adjustable or Fixed Output 1.5V, 2.5V, 2.85V, 3.0V, 3.3V, 3.5V and 5.0V • Output Current of 5A • Low Dropout, 500mV at 5A Output Current • Fast Transient Response • Remote Sense
AMS1505
5A LOW DROPOUT VOLTAGE REGULATORS
APPLICATIONS
• High Current Regulators • Post Regulators for Switching Supplies • Microprocessor Supply • Adjustable Power Supply • Notebook/Personal Computer Supplies
GENERAL DESCRIPTION
The AMS1505 series of adjustable and fixed low dropout voltage regulators are designed to provide 5A output current to The power the new generation of microprocessors. The dropout voltage of the device is 100mV at light loads and rising to 500mV at maximum output current. A second low current input voltage 1V or greater then the output voltage is required to achieve this dropout. The AMS1505 can also be used as a single supply device. New features have been added to the AMS1505: a remote Sense pin is brought out virtually eliminating output voltage variations due to load changes. The typical load regulation, measured at the Sense pin, for a load current step of 100mA to 5A is less than 1mV. The AMS1505 series has fast transient response. The Adjust pin is brought out on fixed devices. To further improve the transient response the addition of a small capacitor on the Adjust pin is recommended. The AMS1505 series are ideal for generating processor supplies of 2V to 3V on motherboards where both 5V and 3.3V supplies are available. The AMS1505 devices are offered in 5 lead TO-220 and TO-263 (plastic DD) packages and in the 7 lead TO-220 package.
ORDERING INFORMATION:
OPERATING JUNCTION 5 LEAD TO-263 5 LEAD TO-220 7 LEAD TO-220 TEMPERATURE RANGE AMS1505CM AMS1505CT AMS1505CT-1.5 0 to 125° C AMS1505CM-1.5 AMS1505CT-1.5 AMS1505CT-2.5 0 to 125° C AMS1505CM-2.5 AMS1505CT-2.5 AMS1505CT-2.85 0 to 125° C AMS1505CM-2.85 AMS1505CT-2.85 AMS1505CT-3.0 0 to 125° C AMS1505CM-3.0 AMS1505CT-3.0 AMS1505CT-3.3 0 to 125° C AMS1505CM-3.3 AMS1505CT-3.3 AMS1505CT-3.5 0 to 125° C AMS1505CM-3.5 AMS1505CT-3.5 AMS1505CT-5.0 0 to 125° C AMS1505CM-5.0 AMS1505CT-5.0 0 to 125° C PACKAGE TYPE
PIN CONNECTIONS
5 LEAD TO-220
5 4 3 2 1 VPOWER VCONTROL OUTPUT ADJUST/GND SENSE
FRONT VIEW 7 LEAD TO-220
7 6 5 4 3 2 1 NC Vpower ADJUST OUTPUT Vcontrol GND SENSE
FRONT VIEW 5 LEAD TO-263
5 4 3 2 1 Vpower Vcontrol OUTPUT ADJUST/GND SENSE
FRONT VIEW
Advanced Monolithic Systems, Inc.
6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
AMS1505
ABSOLUTE MAXIMUM RATINGS (Note 1)
VPOWER Input Voltage 7V VCONTROL Input Voltage 13V Operating Junction Temperature Range Control Section 0°C to 125°C Power Transistor 0°C to 150°C Storage temperature - 65°C to +150°C Soldering information Lead Temperature (10 sec) Thermal Resistance TO-220 package TO-263 package 300°C ϕ JA= 50°C/W ϕ JA= 30°C/W*
* With package soldering to 0.5in2 copper area over backside ground plane or internal power plane ϕ JA can vary from 20°C/W to >40°C/W depending on mounting technique.
ELECTRICAL CHARACTERISTICS
Electrical Characteristics at ILOAD = 0 mA, and TJ = +25°C unless otherwise specified. Parameter
Reference Voltage
Device
AMS1505
Conditions
VCONTROL = 2.75V, VPOWER =2V, ILOAD = 10mA VCONTROL = 2.7V to 12V, VPOWER =3.3V to 5.5V, ILOAD = 10mA to 5A VCONTROL = 4V, VPOWER =2.V, ILOAD = 0mA VCONTROL = 3V, VPOWER =2.3V, ILOAD = 0mA to 5A VCONTROL = 5V, VPOWER =3.3V, ILOAD = 0mA VCONTROL = 4V, VPOWER =3.3V, ILOAD = 0mA to 5A VCONTROL = 5.35V, VPOWER =3.35V, ILOAD = 0mA VCONTROL = 4.4V, VPOWER =3.7V, ILOAD = 0mA to 5A VCONTROL = 5.5V, VPOWER =3.5V, ILOAD = 0mA VCONTROL = 4.5V, VPOWER =3.8V, ILOAD = 0mA to 5A VCONTROL = 5.8V, VPOWER =3.8V, ILOAD = 0mA VCONTROL = 4.8V, VPOWER =4.1V, ILOAD = 0mA to 5A VCONTROL = 6V, VPOWER =4V, ILOAD = 0mA VCONTROL = 5V, VPOWER =4.3V, ILOAD = 0mA to 5A VCONTROL = 7.5V, VPOWER =5.5V, ILOAD = 0mA VCONTROL = 6.5V, VPOWER =5.8V, ILOAD = 0mA to 5A ILOAD = 10 mA , 1.5V≤ (VCONTROL - VOUT) ≤ 12V 0.8V≤ (VPOWER - VOUT) ≤ 5.5V VCONTROL = VOUT + 2.5V, VPOWER =VOUT + 0.8V, ILOAD = 10mA to 5A VCONTROL = 5V, VPOWER =3.3V, VADJ = 0V (Note 3) VCONTROL = VOUT + 2.5V, VPOWER =VOUT + 0.8V, ILOAD = 10mA to 5A VCONTROL = VOUT + 2.5V, VPOWER =VOUT + 0.8V, ILOAD = 10mA to 5A VCONTROL = 2.75V, VPOWER = 2.05V, ILOAD = 10mA (VIN - VOUT) = 5V
Min
1.243 1.237 1.491 1.485 2.485 2.475 2.821 2.833 2.982 2.970 3.280 3.235 3.479 3.430 4.930 4.950
Typ
1.250 1.250 1.500 1.500 2.500 2.500 2.850 2.850 3.000 3.000 3.300 3.300 3.500 3.500 5.000 5.000 1
Max
1.258 1.263 1.509 1.515 2.515 2.525 2.879 2.867 3.018 3.030 3.320 3.333 3.521 3.535 5.030 5.050 3
Units
V V V V V V V V V V V V V V V V mV
Output Voltage
AMS1505-1.5
AMS1505-2.5 AMS1505-2.85 AMS1505-3.0 AMS1505-3.3 AMS1505-3.5 AMS1505-5.0 Line Regulation AMS1505/-1.5/-2.5/ -2.85/-3.0/-3.3/-3.5/-5.0 Load Regulation AMS1505/-1.5/-2.5/ -2.85/-3.0/-3.3/-3.5/-5.0 Minimum Load Current Control Pin Current (Note 4) Ground Pin Current (Note 4) Adjust Pin Current Current Limit AMS1505 AMS1505/-1.5/-2.5/ -2.85/-3.0/-3.3/-3.5/-5.0 AMS1505/-1.5/-2.5/ -2.85/-3.0/-3.3/-3.5/-5.0 AMS1505 AMS1505/-1.5/-2.5/ -2.85/-3.0/-3.3/-3.5/-5.0 Ripple Rejection AMS1505/-1.5/-2.5/ -2.85/-3.0/-3.3/-3.5/-5.0 Thermal Regulation Thermal Resistance Junction-to-Case AMS1505
1
5
mV
5 50
10 85
mA mA
6
10
mA
50 7.1 8.0
120
µA A
VCONTROL = VPOWER = VOUT + 2.5V, VRIPPLE = 1VP-P ILOAD = 2A TA = 25°C, 30ms pulse T Package: Control Circuitry/ Power Transistor M Package: Control Circuitry/ Power Transistor
60
80
dB
0.002
0.020 0.65/2.70 0.65/2.70
%W °C/W °C/W
Advanced Monolithic Systems, Inc.
6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
AMS1505
ELECTRICAL CHARACTERISTICS
Electrical Characteristics at IOUT = 0 mA, and TJ = +25°C unless otherwise specified. Parameter
Dropout Voltage Control Dropout (VCONTROL - VOUT) Power Dropout (VPOWER - VOUT) AMS1505/-1.5/-2.5/ -2.85/-3.0/-3.3/-3.5/-5.0 AMS1505/-1.5/-2.5/ -2.85/-3.0/-3.3/-3.5/-5.0
Device
Conditions
Note 2 VPOWER =VOUT + 0.8V, ILOAD = 10mA VPOWER =VOUT + 0.8V, ILOAD = 5A VCONTROL =VOUT + 2.5V, ILOAD = 10mA VCONTROL =VOUT + 2.5V, ILOAD = 5A
Min
Typ
Max
Units
1.00 1.15 .10 .45
1.15 1.30 0.17 0.50
V V V V
Parameters identified with boldface type apply over the full operating temperature range. Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. For guaranteed specifications and test conditions, see the Electrical Characteristics. The guaranteed specifications apply only for the test conditions listed. Note 2: Unless otherwise specified VOUT = VSENSE. For the adjustable device VADJ = 0V. Note 3: The dropout voltage for the AMS1505 is caused by either minimum control voltage or minimum power voltage. The specifications represent the minimum input/output voltage required to maintain 1% regulation. Note 4: For the adjustable device the minimum load current is the minimum current required to maintain regulation. Normally the current in the resistor divider used to set the output voltage is selected to meet the minimum load current requirement. Note 5: The control pin current is the drive current required for the output transistor. This current will track output current with a ratio of about 1:100. The minimum value is equal to the quiescent current of the device.
PIN FUNCTIONS
Sense (Pin 1): This pin is the positive side of the reference voltage for the device. With this pin it is possible to Kelvin sense the output voltage at the load. Adjust (Pin 2/5): This pin is the negative side of the reference voltage for the device. Adding a small bypass capacitor from the Adjust pin to ground improves the transient response. For fixed voltage devices the Adjust pin is also brought out to allow the user to add a bypass capacitor. GND (Pin 2, 7-Lead only): For fixed voltage devices this is the bottom of the resistor divider that sets the output voltage. VPOWER (Pin 5/6): This pin is the collector to the power device of the AMS1505. The output load current is supplied through this pin. The voltage at this pin must be between 0.1V and 0.8V greater than the output voltage for the device to regulate. VCONTROL (Pin 4/3): This pin is the supply pin for the control circuitry of the device. The current flow into this pin will be about 1% of the output current. The voltage at this pin must be 1.3V or greater than the output voltage for the device to regulate. Output (Pin 3/4): This is the power output of the device.
Advanced Monolithic Systems, Inc.
6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
AMS1505
APPLICATION HINTS
The AMS1505 series of adjustable and fixed regulators are designed to power the new generation of microprocessors. The AMS1505 is designed to make use of multiple power supplies, existing in most systems, to reduce the dropout voltage. One of the advantages of the two supply approach is maximizing the efficiency. The second supply is at least 1V greater than output voltage and is providing the power for the control circuitry and supplies the drive current to the NPN output transistor. This allows the NPN to be driven into saturation; thereby reducing the dropout voltage by a VBE compared to conventional designs. For the control voltage the current requirement is small equal to about 1% of the output current or approximately 50mA for a 5A load. Most of this current is drive current for the NPN output transistor. This drive current becomes part of the output current. The maximum voltage on the Control pin is 13V. The maximum voltage at the Power pin is 7V. Ground pin current for fixed voltage devices is typical 6mA and is constant as a function of load. Adjust pin current for adjustable devices is 60µA at 25°C and varies proportional to absolute temperature. The improved frequency compensation of AMS1505 permits the use of capacitors with very low ESR. This is critical in addressin
