Datasheet MAX882, MAX883, MAX884 (Maxim) - 8

5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators
IN LBI LOW-BATTERY REVERSE- LBO MOSFET DRIVER COMPARATOR P CURRENT WITH FOLDBACK N PROTECTION CURRENT LIMIT ERROR AMP SHUT- OFF DOWN OUT (STBY) LOGIC 1.20V REFERENCE SET DUAL-MODE R1 COMPARATOR THERMAL R2 SENSOR 65mV GND
MAX882/MAX883/MAX884
( ) ARE FOR MAX882. Figure 1. MAX882/MAX883/MAX884 Functional Diagram In adjustable mode, the user selects an output voltage
Standby Mode (MAX882)
in the 1.25V to 11V range by connecting two external The MAX882 has a standby feature that disconnects resistors, used as a voltage-divider, to the SET pin the input from the output when STBY is brought low, but (Figure 2). keeps all other circuitry awake. In this mode, VOUT The output voltage is set by the following equation: drops to 0, and the internal biasing circuitry (including the low-battery comparator) remains on. The maximum ⎛ R1⎞ quiescent current during standby is 15µA. STBY is a V = V OUT SET 1 + ⎝⎜ R2 ⎠⎟ comparator input with the other input internally tied to the reference voltage. Use a resistor network as shown where VSET = 1.20V. in Figure 3 to set a standby-mode threshold voltage for To simplify resistor selection: undervoltage lockout. Connect STBY to IN for normal ⎛ V ⎞ operation. R1 = R2 OUT − 1 ⎝⎜ VSET ⎠⎟
OFF Mode (MAX883/MAX884)
A low-logic input on the OFF pin shuts down the Since the input bias current at SET is nominally zero, MAX883/MAX884. In this mode, the pass transistor, large resistance values can be used for R1 and R2 to control circuit, reference, and all biases are turned off, minimize power consumption without losing accuracy. and the supply current is reduced to less than 1µA. Up to 1.5MΩ is acceptable for R2. Since the VSET toler- LBO is undefined in OFF mode. Connect OFF to IN for ance is less than ±40mV, the output can be set using normal operation. fixed resistors instead of trim pots.
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