1.5A Low Dropout Voltage Regulator Adjustable & Fixed Output Fast Response
PRODUCT DESCRIPTION Calogic's is a low power 1.5A adjustable and fixed voltage regulator. The device requires 2 external resistors to set the output for the adjustable version. The CLM2815 has been designed for low voltage applications that require lower dropout and faster transient responses. The device is well suited to power a low voltage microprocessor that requires a low dropout and a fast transient response to regulate from to 3.8V. The device is adjustable to 1.2 volts. The product family offers full protection against over-current faults, reversed input polarity, reversed load insertion, and positive and negative transient voltage. On-chip trimming adjusts the reference voltage to 1% while delivering 1.5A output current. Encapsulated & TO-252 packages. ORDERING INFORMATION Part CLM2815AT-X CLM2815AAT-X Package TO-220 TO-263 (DD) TO-263 (DD) TO-263 (DD) TO-263 (DD) Temperature Range to +125oC
Adjustable Output. Down To 1.2V Fixed Output Voltages. 3.3, 5.0V Output Current. 1.5A Low Dropout Voltage. 1.1V Typ. Extremely Tight Load And Line Regulation Current & Thermal Limiting Standard 3-Terminal Low Cost & TO-252 Similar To Industry Standard LT1086/LT1586
APPLICATIONS Powering VGA & Sound Card Power PCTM Supplies SMPS Post-Regulator High Efficiency "Green" Computer Systems High Efficiency Linear Power Supplies Portable Instrumentation Constant Current Regulators Adjustable Power Supplies Battery charger
CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025
ABSOLUTE MAXIMUM RATINGS Lead Temp. (Soldering, 10 Seconds). 300oC Storage Temperature Range. to +150oC Operating Junction Temperature Range CLM2815 Control Section. +125oC CLM2815 Power Transistor. -45oC +150oC Input Voltage. 10V Input to Output Voltage Differential. 10V Maximum Output Current. 2AELECTRICAL CHARACTERISTICS (Note 1) at IOUT = 25oC, unless otherwise specified.
PARAMETER 1.5V VERSION Output Voltage (Note 2) 2.5V VERSION Output Voltage (Note 2) 3.3V VERSION Output Voltage (Note 2) 5.0V VERSION Output Voltage (Note 2) ALL VOLTAGE OPTIONS Reference Voltage (VREF) Min. Load Current (Note 3) Line Regulation (VREF (IIN)) Load Regulation (VREF (IOUT)) Dropout Voltage Current Limit (IOUT(MAX)) Long Term Stability Thermal Regulation (VOUT (PWR)) Temperature Stability (VOUT (T)) Output Noise, RMS Thermal Resistance (Note A % %/W % %VO
VIN 7V, P PMAX 1.5V (VIN - VOUT 10mA I OUT IOUT 5.75 1.5V (VIN - VOUT 5.75V 2.75V VIN 7V, IOUT = 125oC (Note 3) VIN 7V, I OUT = 125oC (Note 2) 10mA IOUT 1.5A, (VIN - VOUT 25oC 0 IOUT 1.5A, VIN = 125oC (Note 2) VREF = 1%, IOUT = 1.5A (Note 3), IOUT 1.5A (Note 2) VIN 1.5A 1.4V (VIN - VOUT ) (Note = 125 oC, 1000 Hrs. 25oC, 20ms pulse25oC TO-220 Junction to Tab Junction to Ambient Junction to Tab Junction to Ambient
The Bold specifications apply to the over full operating temperature range. Note 1: Changes in output voltage due to heating effects are covered under the specification for thermal regulation. Note 2: Fixed version only. Note 3: Adustable version only.
APPLICATION HINTS The Calogic Semiconductor CLM2815 incorporates protection against over-current faults, reversed load insertion, over temperature operation, and positive and negative transient voltage. However, the use of an output capacitor is required in order to insure the stability and the performances. Stability The output capacitor is part of the regulator's frequency compensation system. Either a 220�F aluminum electrolytic capacitor a 47�F solid tantalum capacitor between the output terminal and ground guarantees stable operation for all operating conditions. However, in order to minimize overshoot and undershoot, and therefore optimize the design, please refer to the section 'Ripple Rejection'. Ripple Rejection Ripple rejection can be improved by adding a capacitor between the ADJ pin and ground. When ADJ pin bypassing is used, the value of the output capacitor required increases to its maximum (220�F for an aluminum electrolytic capacitor, or 47�F for a solid tantalum capacitor). If the ADJ pin is not bypass, the value of the output capacitor can be lowered to 100�F for an electrolytic aluminum capacitor or 15�F for a solid tantalum capacitor. However the value of the ADJ-bypass capacitor should be chosen with respect to the following equation: C FR R1 ) Where C = value of the capacitor in Farads (select an equal or larger standard value), FR = ripple frequency in Hz, R1 = value of resistor R1 in Ohms. If an ADJ-bypass capacitor is used, the amplitude of the output ripple will be independent of the output voltage. If an ADJ-bypass capacitor is not used, the output ripple will be proportional to the ratio of the output voltage to the reference voltage: M = VOUT / VREF Where M = multiplier for the ripple seen when the ADJ pin is optimally bypassed. VREF = Reference Voltage For the Power Section 104.5oC 109.5oC TJUNCTION MAX for the power transistor. In both cases reliable operation is insured by adequate junction temperature. Reducing parasitic resistance and inductance One solution to minimize parasitic resistance and inductance is to connect in parallel capacitors. This arrangement will improve the transient response of the power supply if your system requires rapidly changing current load condition. Thermal Consideration Although the CLM2815 offers some limiting circuitry for overload conditions, it is necessary not to exceed the maximum junction temperature, and therefore to be careful about thermal resistance. The heat flow will follow the lowest resistance path, which is the Junction-to-case thermal resistance. In order to insure the best thermal flow of the component, a proper mounting is required. Note that the case of the device is electrically connected to the output. In case the case has to be electrically isolated, a thermally conductive spacer can be used. However do not forget to consider its contribution to thermal resistance. Assuming: VIN = 10V, VOUT = 5V, IOUT = 90oC, CASE = 1oC/W (no external heat sink, no wind) Power dissipation under these conditions PD = (VIN - VOUT) IOUT = 7.5W Junction Temperature TA + PD (CASE + JC) For the Control Section 102oC 114oC TJUNCTION MAX for the control section.