Document
MIC5258
Micrel
MIC5258
150mA µCap CMOS LDO Regulator w/Power Good Final Information
General Description
The MIC5258 is an efficient, precise CMOS voltage regulator with power good output. The MIC5258 offers better than 3% initial accuracy, and constant ground current (typically 100µA)over load . The MIC5258 also works with low-ESR ceramic capacitors, reducing the amount of board space necessary for power applications, critical in hand-held wireless devices. Key features include current limit, thermal shutdown, a pushpull output for faster transient response, and an active clamp to speed up device turnoff. Available in the IttyBitty™ SOT-23-5 package, the MIC5258 is a fixed 1.2V regulator.
Features
• • • • • • • • • • Power Good indicator Load independent, ultralow ground current: 100µA 150mA output current Current limiting Thermal shutdown Tight load and line regulation “Zero” off-mode current Stability with low-ESR capacitors Fast transient response TTL-Logic-controlled enable input
Applications
• Processor power-up sequencing • Laptop, notebook, and palmtop computers • PCMCIA VCC and VPP regulation/switching
Ordering Information
Part Number MIC5258-1.2BM5 Marking LN12 Voltage 1.2 Junction Temp. Range* –40°C to +125°C Package SOT-23-5
Other voltages available. Contact Micrel for details.
Typical Application
47k VIN MIC5258-x.xBM5
1 2 Enable Shutdown 3 4 5
VOUT COUT PG
EN
EN (pin 3) may be connected directly to IN (pin 1).
Low-Noise Regulator Application
IttyBitty is a trademark of Micrel, Inc. Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com
September 2001
1
MIC5258
MIC5258
Micrel
Pin Configuration
EN GND IN
3 2 1
LNxx
4 5
PG
OUT
MIC5258-x.xBM5
Pin Description
Pin Number 1 2 3 4 5 Pin Name IN GND EN PG OUT Pin Function Supply Input Ground Enable/Shutdown (Input): CMOS compatible input. Logic high = enable; logic low = shutdown. Do not leave open. Power Good Output Regulator Output
MIC5258
2
September 2001
MIC5258
Micrel
Absolute Maximum Ratings (Note 1)
Supply Input Voltage (VIN) .................................. 0V to +7V Enable Input Voltage (VEN) .................................. 0V to VIN Flag Output Voltage (VPG) ................................... 0V to VIN Junction Temperature (TJ) ...................................... +150°C Storage Temperature ............................... –65°C to +150°C Lead Temperature (soldering, 5 sec.) ....................... 260°C ESD, Note 3
Operating Ratings (Note 2)
Input Voltage (VIN) ......................................... +2.7V to +6V Enable Input Voltage (VEN) .................................. 0V to VIN Flag Output Voltage (VPG) ................................... 0V to VIN Junction Temperature (TJ) ....................... –40°C to +125°C Thermal Resistance SOT-23(θJA) ...................................................... 235°C/W
Electrical Characteristics
VIN = 2.7V, VEN = VIN; IOUT = 100µA; TJ = 25°C, bold values indicate –40°C ≤ TJ ≤ +125°C; unless noted. Symbol VO ∆VLNR ∆VLDR IQ IGND PSRR ILIM Enable Input VIL VIH IEN Enable Input Logic-Low Voltage Enable Input Logic-High Voltage Enable Input Current VIN = 5.5V, regulator shutdown VIN = 5.5V, regulator enabled VIL ≤ 0.4V; VIN = 5.5V VIH ≥ 1.6V; VIN = 5.5V Thermal Protection Thermal Shutdown Temperature Thermal Shutdown Hysteresis Power Good , Note 6 VPG VOL IPG VPG Delay
Note 1. Note 2. Note 3. Note 4. Note 5. Note 6.
Parameter Output Voltage Accuracy Line Regulation Load Regulation Quiescent Current Ground Pin Current, Note 5
Conditions IOUT = 100µA VIN = 2.7V to 6V IOUT = 0.1mA to 150mA, Note 4 VEN ≤ 0.4V (shutdown) PG = NC IOUT = 0mA; VIN = 6.0V IOUT = 150mA; VIN = 6.0V f = 120Hz, COUT = 4.7µF, IOUT = 150mA VOUT = 0V
Min –3 –4 –0.3
Typical
Max 3 4 0.3
Units % % %/V % µA µA µA dB mA
3.5 0.45 110 110 tbd 160 350
4 1 150 150
Power Supply Rejection Current Limit
0.4 1.6 0.01 0.01
V V µA µA °C °C
150 10
Low Threshold High Threshold PG Output Logic-Low Voltage Power Good Leakage Current Delay time to Power Good
% of VOUT (PG ON) % of VOUT (PG OFF) IL = 100µA, fault condition power good off, VPG = 5.5V See Timing Diagram
89 97 0.02 0.01 1 5 0.1
% % V µA ms
Exceeding the absolute maximum rating may damage the device. The device is not guaranteed to function outside its operating rating. Devices are ESD sensitive. Handling precautions recommended. Regulation is measured at constant junction temperature using low duty cycle pulse testing. Parts are tested for load regulation in the load range from 0.1mA to 150mA. Changes in output voltage due to heating effects are covered by the thermal regulation specification. 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. The power good is a function of the output voltage being 5% low and the detection of one of the following: overcurr.