Download presentation
1
MALVINO Electronic PRINCIPLES SIXTH EDITION
2
Regulated Power Supplies
Chapter 24
3
Power supply regulation
Vout Vline RL Load regulation = x 100% VNL - VFL VFL Line regulation = x 100% VHL - VLL VLL
4
A zener diode shunt voltage regulator
RS Power supply Vin Vout VZ RL Vout = VZ Vin - Vout Vout IS = IL = IZ = IS - IL RS RL
5
Improved shunt voltage regulator
RS Power supply Vin Vout VZ RL Vout = VZ + VBE Vin - Vout Vout IS = IL = IC IS - IL RS RL
6
Power supply Zener follower is a series voltage regulator. RS Vin
PD (Vin - Vout)IL Vout = VZ + VBE VZ RL Vout
7
Two-transistor voltage regulator
R3 + R4 R4 (VZ + VBE) Vout = +Vin Vout Q2 R2 R1 R3 RL Q1 R4 VZ
8
Improved voltage regulator
R2 + R3 R3 VZ Vout = +Vin Vout R2 R1 RL R3 VZ
9
Regulator with current limiting
VZ Vout = Q1 +Vin Vout R4 R2 R1 RL R5 Q2 R3 ISL = VBE R4 VZ
10
Simple current-limiting
VL Vreg Constant current region VBE(Q2) 0.6 V IL ISL
11
Foldback current limiting
ISL = VBE KR4 Foldback current limiting Q1 R4 +Vin R6 R2 R1 R7 RL Q2 R5 R3 (1-K)Vout KR4 Imax = ISL + VZ
12
Foldback current-limiting
VL Vreg Foldback current region IL Imax ISL
13
Monolithic regulator with current booster
Vin Q1 1 2 LM78XX Vout R1 3 RL
14
Current booster with current limiting
Q2 Vin Q1 1 2 Vout LM78XX R1 3 RL
15
DC-to-DC converter +Vin R1 Q2 T1 vin Q1 RL Q3 R2
16
Switching regulators The pass transistor is switched between cutoff and saturation. Better efficiency than linear. Topologies: Buck: steps the voltage down Boost: steps the voltage up Buck-boost: inverts the input voltage
17
Buck regulator Q L +Vin D C RL R2 PWM R1 VREF Vout = DVin
18
Boost regulator Vkick Vp L +Vin D Q C RL R2 PWM R1 VREF
Vp = Vin + Vkick
19
Buck-boost regulator Q +Vin D L C RL R2 PWM R1 VREF
20
Monolithic buck regulator
5 4 IN OUT L +Vin D C3 RL C1 LT1074 R2 1 COMP FB 2 3 R1 R3 Vout = R1 + R2 R1 (2.21 V) C2
21
Using the charge pump of the MAX633 IC
+15 V IN OUT 4 5 +Vin C3 CP 6 -12 V C1 MAX633 D2 1,3,7 C2 D1
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.