Document
DC / DC converter for LCDs
BP5311A / BP5311XA
The BP5311A and BP5311XA are DC / DC converters for supplying power to liquid crystal display (LCD) panels. The modules supply a positive voltage for LCDs from a logic circuit power supply (+5). They are available in a single in-line package as an upright (BP5311A) or L-shaped lead (BP5311XA) type.
Applications LCD panels in personal computers and word processors.
Features 1) High conversion efficiency 2) Built-in protection circuit 3) Built-in ON/OFF switch. 4) Compact and light. 5) Surface mounting is possible because parts are concentrated on one side. 6) Available as an upright or L-shaped lead type.
Absolute maximum ratings (Ta=25°C)
Parameter Power supply voltage Operating temperature range Storage temperature range Symbol VIN Topr Tstg Limits 7 0~60 −30~+85 Unit V °C °C
Block diagram
TRANSFORMER
CURRENT SENSOR
SW CTRL
CONTROL CIRCUIT
ON / OFF
9 VIN
8 VCTL
7 GND
4 GND
3 Vref
2 VOUT
1 Co
1/4
Free Datasheet http://www.datasheet4u.com/
BP5311A / BP5311XA
Pin descriptions
Pin No. 1 2 3 4, 7 8 Pin name Co VOUT Vref GND VCTL Function Output smoothing capacitor connection pin ; connect a low-impedance capacitor with a recommended capacitance of 47µF between this and GND. Output pin. Output voltage adjustment pin for contrast ; output voltage is adjusted by connecting a resistor between pins 2 and 3 or pins 3 and 4. Ground pin. Output ON/OFF control pin ; output starts when the pin is HIGH level, and stops when the pin is LOW or OPEN. Input pin ; connect a low-impedance capacitor with a recommended capacitance of 100µF between this pin and GND.
9
VIN
Electrical characteristics
Parameter Input voltage Output current Output voltage Output voltage when OFF Ripple noise voltage Efficiency ON / OFF CTL voltage when ON ON / OFF CTL voltage when OFF ON / OFF CTL current Current consumption when OFF
(unless otherwise noted, Ta=25°C, VCTL=5V, R1~R2 resistors are disconnected)
Symbol VIN IOUT VOUT1 VOUT2 ν1 η VCTL
Min. 4.5 − 28.0 − − 67 1.5 −
Typ. 5.0 − 29.5 − 100 77 − −
Max. 5.5 25 31.0 0.3 200 − − 0.5
Unit V mA V V mVP-P % V
Conditions − − VIN=4.5~5.5V, IOUT=0~25mA VIN=4.5~5.5V, VCTL=0V VIN=5V, IOUT=20mA ∗ VIN=5V, IOUT=20mA VIN=5V, Vo>28V VIN=5V, Vo<0.3V
VCTL
(Alternatively, when OPEN) − − − − 500
V µA µA
ICTL
VIN=5V, VCTL=1.5V
IOFF
50
VIN=5V, VCTL=0V
∗ Measured with a band width of 20 MHz.
Measurement circuit / Application example
BP5311A / BP5311XA
1
2
3
4
7
8
9
Be sure to use fuse for safety
VOUT
R1 R2 VCTL
VIN
+
C2
+
C1
GND
GND
Fig.1
C1 : 100µF / 16V (Low impedance) C2 : 47µF / 35V (Low impedance) R1, 2 : Resistors for adjusting output voltage (Contrast adjustment)
2/4
Free Datasheet http://www.datasheet4u.com/
BP5311A / BP5311XA
Electrical characteristic curves (1) Place I/O external capacitors as near as possible to the connection pins. In particular, make sure to minimize the impedance between the input-side capacitor (C1) and pin 9. A length less than 50 mm is recommended for a copper foil of 1.0 mm wide and 35µm thick. (2) Avoid frequent switching using the ON/OFF CTL pin (five times per second at the maximum). (3) R1 and R2 resistors, which are used for changing the output voltage, are usually not required.
VIN=5V OUTPUT VOLTAGE : Vo (V) OUTPUT VOLTAGE: Vo (V) 25 VIN=5V
35
20
30
15 100k 1M 10M 100k 1M 10M
FEED BACK RESISTANCE : R1 (Ω)
FEED BACK RESISTANCE : R2 (Ω)
Fig.2 Output voltage vs.
Fig.3 Output voltage and
feedback resistance (R1)
feedback resistance (R2)
External dimensions (Units : mm)
BP5311A BP5311XA
26.0 Max.
6.0 Max.
26.0 Max.
6.0 Max.
Unmarked side
14.7 Max.
Unmarked side Marked side
15.5 Max.
Marked side
3±0.5
1 1 2 3 4 7 8 9 0.25±0.05
2
3
4
7
8
9 4.5±1.0
P=2.54±0.2 0.5±0.1 1.3±0.2 1.3±1.2 2.54×8=20.32
P=2.54±0.2 0.5±0.1 1.3±0.2 1.3±1.2 2.54×8=20.32 5.5Max.
0.5Max.
SIP9
SIP9 (L forming)
0.25±0.05
3/4
Free Datasheet http://www.datasheet4u.com/
Precautions on Use of ROHM Power Module
Safety Precautions
1) The products are designed and produced for application in ordinary electronic equipment (AV equipment, OA equipment, telecommunication equipment, home appliances, amusement equipment etc.). If the products are to be used in devices requiring extremely high reliability (medical equipment, transport equipment, aircraft/spacecraft, nuclear power controllers, fuel controllers, car equipment including car accessories, safety devices, etc.) and whose malfunction or operational error may endanger human life and sufficient fail-safe measures, please consult with the Company's sales staff in advance. If product malfunctions may result in serious damage, including that to human life, sufficient fail-safe measures must be taken, including the following: [a] Installation of protection circuits or other protective devices to improve system safety [b] Installation of redundant circuits in the case of single-circuit failure 2) The products are designed for use in a standa.