Details

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BUY LT1121CZ-5 https://www.utsource.net/itm/p/12555211.html

Parameter	Symbol	Conditions	Min	Typ	Max	Unit
Input Voltage	VIN	Operating Range	2.7	-	15.0	V
Output Voltage	VOUT	Fixed Output	-	5.0	-	V
Quiescent Current	IQ	VIN = 5V	-	80	-	μA
Dropout Voltage	VDROPOUT	IOUT = 10mA	-	400	-	mV
Load Regulation	δVL	1mA ≤ IOUT ≤ 150mA	-	0.5	-	%
Line Regulation	δVL	VIN from 4.75V to 16V	-	0.05	-	%
Transient Response	ΔVOUT	Load Step 0mA to 150mA	-	±50	-	mV
PSRR (Power Supply Rejection Ratio)	PSRR	f = 120Hz	-	75	-	dB
Operating Temperature	Toper		-40	-	125	°C

Instructions for Using LT1121CZ-5

1. Input Voltage Setup:

   • Ensure the input voltage is within the operating range of 2.7V to 15.0V.
   • Use appropriate capacitors at the input to stabilize the supply.

2. Output Configuration:

   • The LT1121CZ-5 provides a fixed output voltage of 5.0V.
   • Place a capacitor at the output to ensure stability and reduce noise.

3. Quiescent Current Consideration:

   • Be aware that the quiescent current is around 80μA at 5V input, which can impact battery life in low-power applications.

4. Dropout Voltage Management:

   • Note the dropout voltage is approximately 400mV at 10mA load. Keep this in mind when designing circuits with tight voltage margins.

5. Regulation Parameters:

   • Check the load regulation (0.5%) and line regulation (0.05%) to ensure stable output under varying conditions.
   • For transient response, the output voltage deviation should be within ±50mV for load steps from 0mA to 150mA.

6. Power Supply Rejection Ratio:

   • Utilize the high PSRR of 75dB at 120Hz to minimize the effect of power supply ripple on the output.

7. Temperature Range:

   • The device operates reliably over a temperature range from -40°C to +125°C.

8. Capacitor Selection:

   • Choose capacitors with suitable ESR (Equivalent Series Resistance) to enhance stability and performance.
   • Typical values are 1μF ceramic capacitors for both input and output.

9. PCB Layout:

   • Pay attention to PCB layout practices to minimize noise and parasitic effects, ensuring optimal performance.

10. Testing:

    • After assembly, test the regulator under various load and input conditions to verify it meets the design specifications.

(For reference only)