Automotive Linear Voltage Regulator LDO TLF4277-2EL typical application circuit

Open online SPICE simulator circuit link: atv_LDO_TLF4277-2EL_v1p1_application_circuit.TSC

Low Drop Out Linear Voltage Regulator TLF4277-2EL
Application Circuit

The resistor divider for a specific output voltage can
be calculated as follows:
VQ = ((R1+R2)/R2)*Vref_int
therefore R1 = ((VQ/Vref_int)-1)*R2
For this model, Vref_int = 1.2 V and R2 < 27 kΩ

For VQ_max = 20 V and R1_max = 9*R2_max
therefore R1_max < 243 kΩ

The typical value of Vref_int is specified as typical 1.19 V in
the datasheet, but should be tweaked to actual simulated
value in the design parameters for accurate results.

{ Please double click here to enter design criteria }

{ Select required Voltage }
V_OUT := 5;
{ Select known Resistor: 1 for R1, 2 for R2 }
R1orR2 := 1;
{ Select Value for known Resistor (R1 or R2) }
R := 38k;
{ Vref defined as a typical value of 1.2 V in the datasheet }
Vref := 1.2;
{ Output Capacitance }
C_OUT := 2.2u;
{ Equivalent Series Resistance for CQ }
Resr_cout := 13m;
{ Current Sense Output Resistor }
R_CSO := 820;
{ Current Sense Output Capacitor }
C_CSO := 2.2u;
{ Number of Thermal Model }
{ Ambient Temperature }
T_AMB := 25;

Thermal model description:
Thermal Model = 1: JEDEC 1s0p, 600mm2 cooling area
Thermal Model = 2: JEDEC 1s0p, footprint
Thermal Model = 3: JEDEC 2s2p
Thermal Model = 7: No self-heating, only TEMP value used as temperature

Model performance:
- dynamic behavior partially modelled
- loop behavior is idealized
- the thermal simulations represent an approximation of the actual thermal
behavior of the device according to the JEDEC standards at Power = 2.55 Watts
and Temperature = 85 °C

The TLF4277-2EL is the ideal companion IC to supply active antennas for car
infotainment applications. The adjustable output voltage makes the TLF4277-2EL
capable of supplying the majority of standard active antennas such as: FM/AM,

The TLF4277-2EL is a monolithic integrated low drop out voltage regulator
capable of supplying loads up to 300 mA. TLF4277-2EL provides an adjustable
output voltage in a range from 5 V up to 12 V. The integrated current
monitor function is a unique feature that provides diagnosis and system
protection functionality.

Via the enable function the IC can be disabled to lower the power consumption.

Demoboard: DEMOBOARD TLF4277-2EL

Other circuits
Voltage Regulator Finder
Technical Assistance
Product info: TLF4277-2EL