30mW待机功耗, PSR +S.R. 方案的手机充电器设计:PMP4378
http://www.ti.com/tool/pmp4378
PMP4378是使用ti二次侧同步整流芯片ucc24610、原边控制芯片ucc28713设计的反激式变换器。具有独立的原边控制和副边同步整流结构,可实现精确地恒流、恒压输出,空载功耗小于30mW,达到了六星级电源标准.原边反馈控制消除了光藕,减少了器件数量和成本,体积只有37mmx31mmx15mm。另外,还有掉电保护、输出过压、过流保护、过温保护等功能,并做了电缆0.3V压降补偿;该设计方案通过了传导和辐射测试,并且通过了常温以及高温测试。这些特点使其非常适合应用于手机充电器、适配器及其它小功率应用场合。
下图是PMP4378的样板图
PMP4378的结构图如下:
可以看到方案的二次侧,将整流二极管换做了同步整流芯片ucc24610控制的开关管,极大减少了整流管的损耗,,而且24610采用睡眠、UVLO、工作、轻载多种模式,进一步降低轻载、空载功率,提高了电源效率,也方便了系统的热管理。
下面是PMP4378的主要规格及测试结果:
规格:
No. |
Description |
Symbol |
Min |
Type |
Max |
Unit |
Test condition |
1 |
Rated Input Voltage |
Vin |
100 |
--- |
240 |
Vac |
|
2 |
Input Voltage Range |
Vin(min/max) |
85 |
264 |
Vac |
||
3 |
Input Current |
Irms |
0.4 |
A |
|||
4 |
Rated Input Frequency |
fin |
50 |
60 |
Hz |
||
5 |
Input Frequency Range |
Fin(min/max) |
47 |
63 |
Hz |
||
6 |
Inrush Current |
Irush |
4 |
A |
264V and 2.4A load |
||
7 |
Average Efficiency |
η |
80.3 |
% |
Tested at cable end |
||
8 |
Standby Power |
Pst |
30 |
mW |
85Vac-264Vac |
||
9 |
Output Voltage |
Vout |
5 |
5.5 |
V |
0-2.4A load and 85V-264Vac |
|
10 |
Output Current |
Iout |
2.4 |
A |
85Vac-264Vac |
||
11 |
Rated Output Power |
Pout |
12 |
W |
|||
12 |
Ripple and Noise |
Vripple |
80 |
mVp_p |
115Vac-230Vac and 0-2.4A |
||
13 |
Startup Time |
Stime |
500 |
mS |
115Vac and 2.4A |
||
14 |
Over Shoot |
Vover |
1 |
% |
|||
15 |
Dynamic response |
4.5 |
V |
0.12A-2.28A, 0.1A/us,30ms cycle |
空载功耗:
效率曲线:
负载效率曲线:
USB端的IV曲线:
热试验(环境温度45?C):
Temp record | ||||||
90VAC 50Hz ,Ambient:45℃ | 264VAC 60Hz,Ambient:45℃ | |||||
Thermal Coupler Channel |
Name | Pos | Record Time | CV5V | Record Time | CV5V |
14:00~15:00 | 2.4A | 16:10~17:10 | 2.4A | |||
11 | Input cap | C1 | 67.5ºC | 63.2ºC | ||
15 | Input cap | C2 | 71ºC | 66.3ºC | ||
3 | Input inductor | L1 | 71.9ºC | 63.5ºC | ||
8 | Schonounous MOSFET | Q2 | 68.4ºC | 68ºC | ||
9 | Transformer | T1 Core | 79.4ºC | 76.7ºC | ||
1 | Transformer | T1 Winding | 85.1ºC | 77ºC | ||
17 | Power Switch | Q1 | 73ºC | 73ºC | ||
5 | Output cap | C5 | 63.9ºC | 63.7ºC | ||
7 | Output cap | C3 | 67.8ºC | 67.2ºC | ||
13 | Output rectifier | D2 | 66.4ºC | 66.2ºC | ||
16 | Rect. Bridge diode | DB1 | 73.1ºC | 64.9ºC | ||
10 | UCC28713 | U1 | 71.9ºC | 70.2ºC | ||
4 | UCC24610 | U2 | 64.7ºC | 64.3ºC | ||
actual Ta | Ta=45.5ºC | Ta=46.8ºC |
EMI测试:
1.5m cable with 2R resistor Io=2.4A, 230V, Line
1.5m cable with 2R resistor Io=2.4A, 230V, Neutral
EMI辐射测试:
1.5m cable with 2R resistor Io=2.4A, 230V, HORIZONTAL
1.5m cable with 2R resistor Io=2.4A, 230V, VERTICAL
保护测试
No |
Item |
Test result |
1 |
Input UVP |
Start at 77Vac, Stop at 72Vac |
2 |
Output over current protection |
Ok, 2.55A maximum |
3 |
Output short-circuit protection |
Ok, hiccup mode |
4 |
Output over voltage protection |
Ok, 5.75V maximum |
5 |
Over Temperature protection |
OK |
非常好的设计,感谢分享