MIC5156

Features:

* 4.5mA typical operating current
*<1A typical standby current
* Low external parts count
* Optional current limit (35mV typical threshold)
* 1% initial output voltage tolerance in most configurations
* 2% output voltage tolerance over temperature
* Fixed output voltages of 3.3V, 5.0V (MIC5156)
* Fixed output voltages of 3.3V, 5.0V, 12V (MIC5157)
* Programmable (1.3 to 36V) with 2 resistors (MIC5156/8)
* Internal charge pump voltage tripler (MIC5157/8)
* Enable pin to activate or shutdown the regulator
* Internal gate-to-source protective clamp
* All versions available in DIP and SOP


Application

* Ultrahigh current ultralow dropout voltage regulator
* Constant high-current source
* Low parts count 5.0V to 3.3V computer supply
* Low noise/low-dropout SMPS post regulator
* High-current, current-limited switch


Pinout




Specifications

Supply Input (V_DD ) ........................................................+38V
Enable Input (V_EN ) ........................................... 0.3V to 36V
Gate Output (V_G ) MIC5156.............................................+55V
Charge Pump Node (V_CP ) MIC5157/8.............................+55V
Source Connection (V_S )........................................1.3 to +36V
Flag (V_FLAG ).......................................................0.3 to +40V
Storage Temperature (T_S ) ......................65°C to +150°C
Lead Temperature (soldering 10 sec.).........................300°C


Description

The MIC5156, MIC5157, and MIC5158 Super Low-Dropout (LDO) Regulator Controllers are single IC solutions for high- current low-dropout linear voltage regulation. Super LDO(TM) Regulators have the advantages of an external N-channel power MOSFET as the linear pass element. The MIC5156/7/8 family features a dropout voltage as low as the R  of the external power MOSFET multiplied by the DS(ON) output current. The output current can be as high as the largest MOSFETs can provide.

The MIC5156/7/8 family operates from 3V to 36V. The MIC5156 requires an external gate drive supply to provide the higher voltage needed to drive the gate of the external MOSFET. The MIC5157 and MIC5158 each have an internal charge pump tripler to produce the gate drive voltage. The tripler is capable of providing enough voltage to drive a logic- level MOSFET to 3.3V output from a 3.5V supply and is clamped to 17.5V above the supply voltage. The tripler requires three external capacitors.

The regulator output of MIC5156, MIC5157, and MIC5158 is constant-current limited when the controller detects 35mV across an optional external sense resistor. An active-low open-collector flag indicates a low voltage of 8% or more below nominal output. A shutdown (low) signal to the TTL-compatible enable control reduces controller supply current to less than 1A while forcing the output voltage to ground.

The MIC5156-3.3 and MIC5156-5.0 controllers have inter- nally fixed output voltages. The MIC5156 [adjustable] output is configured using two external resistors. The MIC5157 is a fixed output controller which is externally configured to select either 3.3V, 5.0V, or 12V. The MIC5158 can be configured as a fixed 5V controller or programmed to any voltage from 1.3V to 36V using two external resistors.

The MIC5156 is available in an 8-pin DIP or SOP. The MIC5157 and MIC5158 are available in a 14-pin DIP or SOP which operate from 40°C to +85°C.