MIC2549A-1BTS Micrel Inc, MIC2549A-1BTS Datasheet
MIC2549A-1BTS
Specifications of MIC2549A-1BTS
Related parts for MIC2549A-1BTS
MIC2549A-1BTS Summary of contents
Page 1
... The MIC2545A/49A’s open-drain flag output is used to indi- cate current-limiting or thermal shutdown to a local controller. The MIC2549A has an additional internal latch which turns the output off upon thermal shutdown, providing robust fault control. The enable signal is compatible with both 3V and 5V logic, and is also used as the thermal shutdown latch reset for the MIC2549A ...
Page 2
... Active High MIC2545A-1YTS Active High MIC2545A-2YM Active Low MIC2545A-2YN Active Low MIC2545A-2YTS Active Low MIC2549A-1BM Active High MIC2549A-1BN Active High MIC2549A-1BTS Active High MIC2549A-2BM Active Low MIC2549A-2BN Active Low MIC2549A-2BTS Active Low MIC2549A-1YM Active High MIC2549A-1YN Active High MIC2549A-1YTS Active High ...
Page 3
... Do not float. MIC2549A only: Also resets thermal shutdown latch. FLG Fault Flag (Output): Active-low, open-drain output. Indicates overcurrent or thermal shutdown. MIC2549A only: Latched low on thermal shutdown. GND Ground: Supply return. ILIM Current Limit: Sets current limit threshold using an external resistor (R connected to ground. 76.8 < Supply Input: Output MOSFET drain ...
Page 4
... Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF. 4. Assumes 4 layer PCB is used Current limit is determined by: LIMIT 6. Off is 0.8V and on is 2.4V for the MIC2545A-1 and MIC2549A-1. Off is enable input has about 100mV of hysteresis. 7. Guaranteed by design but not production tested. M9999-041204 Operating Ratings (1) Supply Voltage (V ...
Page 5
MIC2545A/2549A Test Circuit V OUT Timing Diagrams OUT OUT April 2004 I Device OUT Under OUT Test 90% 90% 10% Functional Characteristics Test Circuit ...
Page 6
... MIC2545A/2549A EN V OUT I LIMIT OUT FLG Figure 2a. MIC2549A-2 Timing: Output Is Reset By Toggling OUT I LIMIT OUT FLG M9999-041204 Short-Circuit Fault Thermal Shutdown Reached Short-Circuit Fault Fault Removed Thermal Shutdown Reached Figure 2b. MIC2545A-2 Timing 6 Output Reset Fault Removed April 2004 Micrel ...
Page 7
MIC2545A/2549A Typical Characteristics Output On-Resistance vs. Supply Voltage 2.5 3.0 3.5 4.0 4.5 5.0 5.5 SUPPLY VOLTAGE (V) On-State Supply Current vs. Temperature 140 ...
Page 8
MIC2545A/2549A Typical Characteristics cont’d 1500 1400 1300 1200 1100 1000 900 800 700 600 500 -40 -20 M9999-041204 Current Limit vs. Temperature 1200 1100 R = 230 SET I TH 1000 I 900 SET 800 I ...
Page 9
MIC2545A/2549A Functional Characteristics Turn-On Response 500mA MIC2545A-1 TIME (500 s/div.) Current-Limit Response Load Removed Thermal Shutdown Current-Limit Threshold 1.12A ( SET MIC2545A-1 TIME (100ms/div.) Enable Into Short Circuit Short-Circuit Current 820mA Thermal V Shutdown IN R SET ...
Page 10
MIC2545A/2549A Functional Characteristics cont’d M9999-041204 Thermal Shutdown (Output Reset by Toggling Enable—MIC2549-1) Ramped Load to a Short Output Reset Output Latched Thermal Shutdown TIME (100ms/div.) 10 Micrel April 2004 ...
Page 11
... MIC2545A/2549A Block Diagram EN OSC. CHARGE PUMP RESET April 2004 THERMAL SHUTDOWN REFERENCE GATE CONTROL THERMAL SHUTDOWN LATCH (MIC2549A) GND 11 IN 1.2V IN ILIM CURRENT LIMIT R SET OUT OUT FLG M9999-041204 Micrel ...
Page 12
... C. Overtemperature detection functions only when the switch is enabled. The MIC2549A features an internal latch which causes the part to remain off after thermal shutdown until a reset pulse is provided via the enable pin (pin 1). While in current-limit, the thermal shutdown latch prevents on/off cycling of the output ...
Page 13
... MIC2545A/2549A Applications Information Supply Filtering A 0 bypass capacitor from IN to GND, located near the MIC2545A and MIC2549A, is strongly recommended to control supply transients. Without a bypass capacitor, an output short may cause sufficient ringing on the input (from supply lead inductance) to damage internal control circuitry. ...
Page 14
MIC2545A/2549A "Hot" Receptacle GND M9999-041204 MIC2545A OUT 2 7 FLG IN 0.1 µ GND OUT LIM C 0.1µF Adaptor Card Figure 5. Hot-Plug Application 14 Backend Function BULK ...
Page 15
MIC2545A/2549A Package Information 0.018 (0.57) 0.026 (0.65) 0.157 (3.99) 0.150 (3.81) 0.064 (1.63) 0.045 (1.14) April 2004 PIN 1 DIMENSIONS: INCH (MM) 0.380 (9.65) 0.370 (9.40) 0.135 (3.43) 0.125 (3.18) 0.380 (9.65) 0.130 (3.30) 0.320 (8.13) 0.100 (2.54) 0.0375 (0.952) ...
Page 16
... TEL This information is believed to be accurate and reliable, however no responsibility is assumed by Micrel for its use nor for any infringement of patents or other rights of third parties resulting from its use. No license is granted by implication or otherwise under any patent or patent right of Micrel Inc. M9999-041204 4.50 (0.177) DIMENSIONS: 6 ...