MIC5504-XYMT

Part: MIC5501/2/3/4 from Micrel

Type: Low Dropout Regulator (LDO)

Key Specs:

• Output Current: 300mA
• Initial Accuracy: ±2%
• Dropout Voltage: 160mV @ 300mA
• Quiescent Current: 38μA (typical)
• Input Voltage Range: 2.5V to 5.5V
• Fixed Output Voltages: 1.0V to 3.3V
• Operating Junction Temperature: –40°C to 125°C

Features:

• Input voltage range: 2.5V to 5.5V
• Fixed output voltages from 1.0V to 3.3V
• 300mA guaranteed output current
• High output accuracy (±2%)
• Low quiescent current: 38μA
• Stable with 1μF ceramic output capacitors
• Low dropout voltage: 160mV @ 300mA
• Output discharge circuit (MIC5502, MIC5504)
• Internal enable pull-down (MIC5503, MIC5504)
• Thermal-shutdown and current-limit protection

Applications:

• Smart phones
• DSC, GPS, PMP, and PDAs
• Medical devices
• Portable electronics
• 5V systems

Package:

• 4-lead Thin DFN: 1.0mm × 1.0mm
• 5-pin SOT23

• Input voltage range: 2.5V to 5.5V
• Fixed output voltages from 1.0V to 3.3V
• 300mA guaranteed output current
• High output accuracy (±2%)
• Low quiescent current: 38μA
• Stable with 1μF ceramic output capacitors
• Low dropout voltage: 160mV @ 300mA
• Output discharge circuit: MIC5502, MIC5504
• Internal enable pull-down: MIC5503, MIC5504
• Thermal-shutdown and current-limit protection
• 4-lead 1.0mm × 1.0mm Thin DFN package
• MIC5504 5-pin SOT23 package

• Smart phones
• DSC, GPS, PMP, and PDAs
• Medical devices
• Portable electronics
• 5V systems

(Top View)

5-Pin SOT23 (M5) (Top View)

Pin Description

VIN = VEN = VOUT + 1V; CIN = COUT = 1μF; IOUT = 100μA; TJ = 25°C, bold values indicate –40°C to +125°C, unless noted.

Notes:

5. Exceeding the absolute maximum rating may damage the device.

6. The device is not guaranteed to function outside its operating rating.

7. The maximum allowable power dissipation of any TA (ambient temperature) is PD(max) = (TJ(max) – TA) / θJA. Exceeding the maximum allowable power dissipation will result in excessive die temperature, and the regulator will go into thermal shutdown.

8. Devices are ESD sensitive. Handling precautions are recommended. Human body model, 1.5kΩ in series with 100pF.

9. Specification for packaged product only.

10. Regulation is measured at constant junction temperature using low duty cycle pulse testing. Changes in output voltage due to heating effects are covered by the thermal regulation specification.

11. Dropout voltage is defined as the input-to-output differential at which the output voltage drops 2% below its nominal value measured at 1V differential. For outputs below 2.5V, dropout voltage is the input-to-output differential with the minimum input voltage 2.5V.

12. Ground pin current is the regulator quiescent current. The total current drawn from the supply is the sum of the load current plus the ground pin current.

• Enable Voltage (VEN)–0.3V to VIN
• Power Dissipation (PD)Internally Limited(7)
• Lead Temperature (soldering, 10s) 260°C
• Junction Temperature (TJ) –40°C to +150°C
• Storage Temperature (Ts) –65°C to +150°C
• ESD Rating(8)
  3kV

The MIC5501/2/3/4 is designed to provide 300mA of continuous current in a very small package. Maximum ambient operating temperature can be calculated based on the output current and the voltage drop across the part. For example if the input voltage is 3.6V, the output voltage is 2.8V, and the output current = 300mA. The actual power dissipation of the regulator circuit can be determined using Equation 1:

$mathbf{P_D} = (mathbb{V}_mathbb{N} - mathbb{V}_mathbb{Ocupmathbb{T}¹}) mid_mathbb{Ocupmathbb{T}} + mathbb{V}_mathbb{N} mid_mathbb{G×mathbb{D}} qquadqquadqquadmathsf{Eq}. mathsf{T}$

Because this device is CMOS and the ground current is typically <100μA over the load range, the power dissipation contributed by the ground current is < 1% and can be ignored for this calculation:

$mathsf{P_D} &= (3.6mathsf{V} - 2.8mathsf{V}) × 300 mathsf{mA} mathsf{P_D} &= 0.240 mathsf{W}$

To determine the maximum ambient operating temperature of the package, use the junction-to-ambient thermal resistance of the device and Equation 2:

$mathsf{P}_mathsf{D(mathsf{max})} = ≤ft(frac{mathsf{T}_mathsf{J(mathsf{max})} - mathsf{T}_mathsf{A}}{θ_mathsf{JA}}right) tag{mathsf{Eq. 2}}$

TJ(max) = 125°C, the maximum junction temperature of the die, θJA thermal resistance = 250°C/W for the DFN package.

Substituting PD for PD(max) and solving for the ambient operating temperature will give the maximum operating conditions for the regulator circuit. The junction-toambient thermal resistance for the minimum footprint is 250°C/W.

The maximum power dissipation must not be exceeded for proper operation.

For example, when operating the MIC5501-MYMT at an input voltage of 3.6V and 300mA load with a minimum footprint layout, the maximum ambient operating temperature TA can be determined as follows:

0.240W = (125°C – TA)/(250°C/W) TA = 65°C

Therefore, the maximum ambient operating temperature allowed in a 1mm × 1mm DFN package is 65°C. For a full discussion of heat sinking and thermal effects on voltage regulators, refer to the "Regulator Thermals" section of Micrel's Designing with Low-Dropout Voltage Regulators handbook. This information can be found on Micrel's website at:

http://www.micrel.com/\_PDF/other/LDOBk\_ds.pdf