E-L4971 Datasheet, PDF (4/13 Pages) STMicroelectronics – 1.5A STEP DOWN SWITCHING REGULATOR

L4971
Table 5. (T_j = 25°C, Cosc = 2.7nF, Rosc = 20kΩ, V_CC = 24V, unless otherwise specified.)
* Specification Refered to T_j from 0 to 125°C
Soft Start
Soft start charge current
30
40
50
Soft start discharge current
6
10
14
Inhibit
V_LL
Low level voltage
*
0.9
I_sLL
Isource Low level
*
5
15
DC Characteristics
Iqop
Total operating quiescent
current
4
6
Iq
Quiescent current
Duty Cycle = 0; V_FB = 3.8V
2.5
3.5
Iqst-by
Total stand-by quiescent
current
V_inh <0.9V
Vcc = 55V; Vinh<0.9V
100 200
150 300
Error Amplifier
V_FB
Voltage Feedback Input
3.33 3.36 3.39
R_L
Line regulation
Vcc = 8 to 55V
5
10
Ref. voltage stability vs
temperature
*
0.4
V_oH
High level output voltage
V_FB = 2.5V
10.3
V_oL
Low level output voltage
V_FB = 3.8V
0.65
Io source Source output current
V_comp = 6V; V_FB = 2.5V
200 300
Io sink Sink output current
V_comp = 6V; V_FB= 3.8V
200 300
I_b
Source bias current
2
3
SVRR E/A Supply voltage ripple rejection V_comp = V_fb; V_cc = 8 to 55V
60
80
DC open loop gain
R_L = ∞
50
57
gm
Transconductance
I_comp = -0.1 to 0.1mA
2.5
V_comp = 6V
Oscillator Section
Ramp Valley
0.78 0.85 0.92
Ramp peak
Vcc = 8V
2
2.15 2.3
Vcc = 55V
9
9.6 10.2
Maximum duty cycle
95
97
Maximum Frequency
Duty Cycle = 0% ;
300
R_osc = 13kΩ, C_osc = 820pF
µA
µA
V
µA
mA
mA
µA
µA
V
mV
mV/°C
V
V
µA
µA
µA
dB
dB
ms
V
V
V
%
kHz
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