Datasheet MAX8887, MAX8888 (Maxim) - 7

Low-Dropout, 300mA Linear Regulators in SOT23 MAX8887/MAX8888
IN SHDN ERROR MOS DRIVER P AMP WITH ILIMIT SHUTDOWN LOGIC OUT MAX8888 POK THERMAL 1.25V 95% POK SENSOR REF REF GND Figure 1. Functional Diagram stability and optimum transient response. Surface-mount
MAXIMUM OUTPUT CURRENT
ceramic capacitors have very low ESR and are com-
vs. INPUT VOLTAGE
monly available in values up to 10µF. Connect CIN and
(POWER DISSIPATION LIMIT)
COUT as close to the MAX8887/MAX8888 as possible to 400 minimize the impact of PC board trace inductance. TA = +85°C TA = +70°C
Noise, PSRR, and Transient Response
MAXIMUM RECOMMENDED OUTPUT CURRENT The MAX8887/MAX8888 are designed to operate with 300 low dropout voltages and low quiescent currents in bat- tery-powered systems while still maintaining excellent noise, transient response, and AC rejection. See the 200 Typical Operating Characteristics for a plot of power- supply rejection ratio (PSRR) versus frequency. When operating from noisy sources, improved supply-noise 100 rejection and transient response can be achieved by MAXIMUM OUTPUT CURRENT (mA) = +3.3V = +2.85V = +1.8V increasing the values of the input and output bypass V OUT V OUT capacitors and through passive filtering techniques. V OUT 0 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Input-Output (Dropout) Voltage
(VIN - VOUT) (V) A regulator’s minimum input-to-output voltage differen- tial (dropout voltage) determines the lowest usable sup- ply voltage at which the output is regulated. In Figure 2. Power Operating Regions: Maximum Output Current vs. Input Voltage battery-powered systems, this determines the useful end-of-life battery voltage. The MAX8887/MAX8888 use a p-channel MOSFET pass transistor. Its dropout volt- age is a function of drain-to-source on-resistance (RDS(ON)) multiplied by the load current (see the Typical Operating Characteristics). VDROPOUT = VIN - VOUT = RDS(ON) ✕ IOUT
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