The EC49315 is a low noise 500mA fixed /adjustable output voltage, with high ripple rejection ratio and fast
transient response. It includes a precise reference voltage, an error amplifier, driver transistors, a compensation
network and a low ON-resistance power MOSFET. It also integrates many protection circuitries, such as current
limiters and an over temperature protection module. The EC49315 works well with low ESR ceramic capacitors,
suitable for battery-powered applications with stringent space requirements and demanding performance. It
also offers low quiescent current.
◆Wide 2.5V to 6V Operating Range
◆Current Limiting Protection
◆Thermal Shutdown Protection
◆Low Dropout : 225mV @ 300mA; VOUT = 3.3V
◆High Ripple Rejection 65dB@10Hz
◆Standby Current Less Than 0.1μA
EC49315 XX XX X
R：Tape & reel
W： A~Z=1~26 weeks
Chip Enable (Active High). Note that this pin is high impedance.
There should be a pull low 100k resistor connected to GND
when the control signal is floating.
Feedback pin voltage is set to be 0.8V, Output voltage can be
programmed by a resistor divider.
No Internal Connection (Floating or Connecting to GND).
Typical Application Circuit
Absolute Maximum Ratings (Note 1)
◆Supply Voltage VIN 8V
◆ Power Dissipation, PD @ TA=25°C
◆ Thermal Resistance, JA
◆ Lead Temperature 260°C
◆ Storage Temperature -65°C to 150°C
◆ ESD Susceptibility
HBM (Human Body Mode) 2kV
MM (Machine Mode) 200V
Recommended Operating Conditions
◆ Input Voltage VIN 2.5V to 6V
◆ EN Input Voltage 0V to 6V
◆ Junction Temperature -40°C to 125°C
◆ Ambient Operating Temperature -40°C to 85°C
Electrical Characteristics (Unless otherwise specified. VIN=5V， TA = 25°C)
Operating Voltage Range
Shutdown Supply Current
VEN = GND, Shutdown
Supply Current Limit
RLOAD = 1Ω
VADJ = 1V
IOUT = 300mA
IOUT = 500mA
VIN = (VOUT +1V) to 6V,
IOUT = 1mA
(Vin=Vout+1V)1mA < IOUT
Fixed Output Voltage Accuracy
VIN = 2.5V to 6V, Shutdown
VIN = 2.5V to 6V, Start-Up
f = 10Hz
COUT = 2.2F, IOUT = 10mA
Thermal Shutdown Temperature
Thermal Shutdown Temperature
Note 1: Stresses listed as the above “Absolute Maximum Ratings” may cause permanent damage to the device.
These are for stress ratings. Functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may remain possibility to affect device reliability.
Note 2: VIN(MIN) = VOUT+VDROP
Note 3: The dropout voltage is defined as (VIN-VOUT) when VOUT is 100mV below the target value of VOUT.
Note 4: The maximum output current is defined as (VIN-VOUT) x IOUT < Power dissipation value.
Function Block Diagram
An input capacitance of 1μF is required between the device input pin and ground directly (the amount of the
capacitance may be increased without limit). The input capacitor MUST be located less than 1cm from the
device to assure input stability. A lower ESR capacitor allows the use of less capacitance, while higher ESR
type (like aluminum electrolytic) requires more capacitance. Capacitor types (aluminum, ceramic and tantalum)
can be mixed in parallel, but the total equivalent input capacitance/ESR must be defined as above for stable
operation. There are no requirements for the ESR on the input capacitor, but tolerance and temperature
coefficient must be considered when selecting the capacitor to ensure the capacitance is 1μF over the entire
The EC49315 is designed specifically to work with very small ceramic output capacitors. The minimum capacitance
recommended(temperature characteristics of X7R, X5R, Z5U or Y5V) is within the 1μF to 10mf range with
5mΩ to 50mΩ ESR range ceramic capacitor between LDO output and GND for transient stability, but it may be
increased without limit. Higher capacitance values help to improve transient response. The output capacitor's
ESR is critical because it forms a zero to provide phase lead which is required for loop stability.
The EC49315 is shut down by pulling the EN pin low, and turned on by driving the input high. If the shutdown
feature is not required, the EN pin should be tied to VIN to keep the regulator on at all times (the EN pin MUST NOT be left floating). To assure proper operation, the signal source used to drive the EN pin must be able to
swing above and below the specified turn-on/off voltage thresholds listed in the “Electrical Characteristics” under VIH
and VIL. The ON/OFF signal may come from either CMOS output, or an open-collector output with pull up resistor to the
device input voltage or another logic supply. The high-level voltage may exceed the device input voltage, but must remain
within the absolute maximum ratings for the EN pin.
For continuous operation, do not exceed the maximum operation junction temperature 125∘C. The maximum
power dissipation depends on the thermal resistance of IC package, PCB layout, the rate of surroundings airflow
and temperature difference between junctions to ambient. The maximum power dissipation can be calculated
by following formula:
Where TJ(MAX) is the maximum operation junction temperature 125∘C, TA is the ambient temperature and
theθJA is the junction to ambient thermal resistance. For recommended operating conditions specification of
EC49315 where TJ(MAX) is the maximum junction temperature of the die (125∘C) and TA is the maximum
ambient temperature. The junction to ambient thermal resistance θJA is layout dependent.
The adjustable version of the EC49315 has an output voltage ranging from 0.9V to 5V. The output voltage of
the EC49315 adjustable regulator is programmed using an external resistor divider as shown in Figure2.
R2 resistor must less than 100KΩ for good stability. To enable default output voltage (pre-set), connect
ADJ pin to ground. There is no external component needed to decide voltage.
DIMENSIONS IN MILLIMETERS
DIMENSIONS IN INCH
DIMENSIONS IN MILLIMETERS
1. All dimensions are in millimeters.
2. Dimension D does not include mold flash, protrusion or gate burrs. Mold flash protrusions or gate burrs shall not exceed 0.15mm per end. Dimension E1 does not include interlead flash or protrusion. Interlead flash or protrusion shall not exceed 0.15mm per side.
3. The package top may be smaller then the package bottom. Dimensions D and E1 are determined at outermost extremes of the plastic body exclusive of mold flash, Tie bar burrs, Gate burrs and interlead flash, but including any mismatch between the top and bottom of the plastic body.
4. Dimension “b” does not include dambar protrusion. Allowable dambar protrusion shall be 0.08mm total in excess of the “b” dimension at maximum material condition. The dambar cannot be located on the lower radius of the foot. Minimum space between protrusion and an adjacent lead shall not be less than 0.07mm