Fujitsu MB3887 Schematic

FUJITSU SEMICONDUCTOR

DATA SHEET

DS04-27709-4E

ASSP F or Pow er Supply Applications (Secondary battery)

DC/DC Converter IC for Charging Li-ion battery

MB3887

DESCRIPTION

■

The MB3887 is a DC/DC converter IC suitable for down-conversion, using pulse-width (PWM) charging and enabling output voltage to be set to any desired level from one cell to four cells. These ICs can dynamically control the secondary batter y’s charge current by detecting a voltage drop in an AC adapter in order to keep its power constant (dynamically-controlled charging) . The charging method enables quick charging, f or example, with the A C adapter during operation of a notebook PC.

The MB3887 provides a broad power supply voltage range and low standby current as well as high efficiency, making it ideal for use as a built-in charging device in products such as notebook PC. This product is covered by US Patent Number 6,147,477.

FEATURES

■

• Detecting a voltage drop in the AC adapter and dynamically controlling the charge current (Dynamically-controlled charging)

(Continued)

PACKAGE

■

24-pin plastic SSOP

(FPT-24P-M03)

MB3887

(Continued)

• Output voltage setting using external resistor : 1 cell to 4 cells

• High efficiency : 96% (VIN = 19 V, Vo = 16.8 V)

• Wide range of operating supply voltages : 8 V to 25 V

• Output voltage setting accuracy : 4.2 V ± 0.74% (T a = −10 °C to +85 °C , per cell)

• Charging current accuracy : ±5%

• Built-in frequency setting capacitor enables frequency setting using external resistor only

• Oscillation frequency range : 100 kHz to 500 kHz

• Built-in current detection amplifier with wide in-phase input voltage range : 0 V to VCC

• In standby mode, leave output voltage setting resistor open to prevent inefficient current loss

• Built-in standby current function : 0 µA (standard)

• Built-in soft-start function independent of loads

• Built-in totem-pole output stage supporting P-channel MOS FET devices

2

PIN ASSIGNMENT

■

−INC2 :

OUTC2 :

+INE2 :

−INE2 :

FB2 :

VREF :

FB1 :

MB3887

(TOP VIEW)

: +INC2

1

2

3

4

5

6

7

24

: GND

23

: CS

22

: VCC (O)

21

: OUT

20

: VH

19

: VCC

18

−INE1 :

+INE1 :

OUTC1 :

OUTD :

−INC1 :

10

11

12

: RT

8

9

17

16

15

14

13

: −INE3

: FB3

: CTL

: +INC1

(FPT-24P-M03)

3

MB3887

PIN DESCRIPTION

■

Pin No. Symbol I/O Descriptions

1 −INC2 I Current detection amplifier (Current Amp2) input terminal. 2 OUTC2 O Current detection amplifier (Current Amp2) output terminal. 3 +INE2 I Error amplifier (Error Amp2) non-inverted input terminal. 4 −INE2 I Error amplifier (Error Amp2) inverted input terminal. 5 FB2 O Error amplifier (Error Amp2) output terminal. 6 VREF O Reference voltage output terminal. 7 FB1 O Error amplifier (Error Amp1) output terminal. 8 −INE1 I Error amplifier (Error Amp1) inverted input terminal 9 +INE1 I Error amplifier (Error Amp1) non-inverted input terminal.

10 OUTC1 O Current detection amplifier (Current Amp1) output terminal.

With IC in standby mode, this terminal is set to “Hi-Z” to prevent loss

11 OUTD O

of current through output voltage setting resistance.

Set CTL terminal to “H” level to output “L” level. 12 −INC1 I Current detection amplifier (Current Amp1) input terminal. 13 +INC1 I Current detection amplifier (Current Amp1) input terminal.

Power supply control terminal. 14 CTL I

15 FB3 O Error amplifier (Error Amp3) output terminal. 16 −INE3 I Error amplifier (Error Amp3) inverted input terminal.

17 RT ⎯ 18 VCC ⎯ Power supply terminal for reference power supply and control circuit.

19 VH O Power supply terminal for FET drive circuit (VH = VCC − 6 V) . 20 OUT O External FET gate drive terminal. 21 VCC (O) ⎯ Output circuit power supply terminal. 22 CS ⎯ Soft-start capacitor connection terminal. 23 GND ⎯ Ground terminal. 24 +INC2 I Current detection amplifier (Current Amp2) input terminal.

Setting the CTL terminal at “L” level places the IC in the standby

mode.

Triangular-wave oscillation frequency setting resistor connection

terminal.

4

BLOCK DIAGRAM

O

)

■

−INE1 UTC1

+INC1

−INC1

+INE1

FB1

−INE2

8

10

13 12

9

7 4

+

× 20

−

VREF

−

+

+ + +

−

<OUT>

Drive

MB3887

21

VCC (O

20

OUT

2

UTC2

+INC2

−INC2

+INE2

FB2

−INE3

OUTD

FB3

CS

24

1 3

5

16

11

15

<SOFT>

VREF

22

+

× 20

−

10 µA

VREF

−

+

VREF

− +

+

4.2 V

45 pF

VCC

Bias

Voltage

<VH>

<UVLO>

(VCC UVLO)

4.2 V

<OSC>

17 6 23 RT

bias

VREF

2.5 V

1.5 V

0.91 V

(0.77 V)

VREF UVLO

VREF

5.0 V

(V

CC

215 kΩ

+

35 kΩ

−

VCC

GND

− 6 V)

VCC

19

18 14

VH

VCC CTL

5

MB3887

ABSOLUTE MAXIMUM RATINGS

■

Parameter Symbol Conditions

Unit

Min Max

Rating

Power supply voltage V Output current I

Peak output current I Power dissipation P

Storage temperature T

CC

OUT

STG

VCC, VCC (O) terminal*

⎯⎯60 mA

Duty ≤ 5 % (t = 1 / f

D

Ta ≤ +25 °C ⎯ 740*

× Duty)

OSC

⎯−55 +125 °C

2

⎯ 28 V

⎯ 700 mA

1

mW

*1 : The package is mounted on the dual-sided epoxy board (10 cm × 10 cm) . *2 : Refer to “ THE SEQUENCE OF THE START-UP AND OFF OF THE POWER SUPPLY” for details. WARNING: Semiconductor devices can be permanently damaged by application of stress (voltage, current,

temperature, etc.) in excess of absolute maximum ratings. Do not exceed these ratings.

6

RECOMMENDED OPERATING CONDITIONS

■

MB3887

Parameter Symbol Conditions

Power supply voltage V Reference voltage output

current

I

VH terminal output current I

V

Input voltage

V

OUTD terminal output voltage V OUTD terminal output current I

OUTD

CTL terminal input voltage V Output current I

Peak output current I Oscillation frequency f

Timing resistor R Soft-start capacitor C

CC

REF

VH

INE

INC

OUTD

CTL

OUT

OSC

T

S

Value

Unit

Min Typ Max

VCC, VCC (O) terminal* 8 ⎯ 25 V

⎯

−INE1 to −INE3, +INE1, +INE2 terminal

+INC1, +INC2, −INC1,

−INC2 terminal

−1 ⎯ 0mA

0 ⎯ 30 mA 0 ⎯ V

0 ⎯ V

− 1.8 V

CC

⎯ 0 ⎯ 17 V ⎯ 0 ⎯ 2mA ⎯ 0 ⎯ 25 V ⎯−45 ⎯+45 mA

Duty ≤ 5 % (t = 1 / fosc × Duty)

−600 ⎯+600 mA

⎯ 100 290 500 kHz ⎯ 27 47 130 kΩ ⎯⎯0.022 1.0 µF

V

VH terminal capacitor C Reference voltage output

capacitor

C

Operating ambient temperature

VH

REF

Ta ⎯−30 +25 +85 °C

⎯⎯0.1 1.0 µF ⎯⎯0.1 1.0 µF

* : Refer to “ THE SEQUENCE OF THE START-UP AND OFF OF THE POWER SUPPLY” for details. WARNING: The recommended operating conditions are required in order to ensure the normal operation of the

semiconductor device. All of the device’s electrical characteristics are warranted when the device is operated within these ranges.

Always use semiconductor devices within their recommended operating condition ranges. Operation outside these ranges may adversely affect reliability and could result in device failure.

No warranty is made with respect to uses, operating conditions, or combinations not represented on the data sheet. Users considering application outside the listed conditions are advised to contact their FUJITSU representatives beforehand.

7

MB3887

ELECTRICAL CHARACTERISTICS

■

Parameter

Sym-

bol

(Ta = +25 °C, VCC = 19 V, VCC (O) = 19 V, VREF = 0 mA)

Pin No.

Conditions

Min Typ Max

Value

Unit

1. Reference voltage block [REF]

2. Under voltage lockout protection circuit block [UVLO]

3. Soft-start block [SOFT]

4. Triangular waveform oscillator circuit block [OSC]

V

REF1

6Ta = +25 °C 4.967 5.000 5.041 V

Output voltage

V

REF2

6Ta = −10 °C to +85 °C 4.95 5.00 5.05 V Input stability Line 6 VCC = 8 V to 25 V ⎯ 310mV Load stability Load 6 VREF = 0 mA to −1 mA ⎯ 110mV Short-circuit output

current

Ios 6 VREF = 1 V −50 −25 −12 mA

V

TLH

VCC = VCC (O) ,

18

VCC =

6.2 6.4 6.6 V

Threshold voltage

V

Hysteresis width V

V

THL

H

TLH

VCC = VCC (O) ,

18

VCC =

5.2 5.4 5.6 V

18 VCC = VCC (O) ⎯ 1.0* ⎯ V

6VREF = 2.6 2.8 3.0 V Threshold voltage

V

Hysteresis width V

Charge current I

Oscillation frequency

f

THL

CS

OSC

6VREF = 2.4 2.6 2.8 V

6 ⎯⎯0.2 ⎯ V

H

22 ⎯−14 −10 −6 µA

20 RT = 47 kΩ 260 290 320 kHz

Frequency temperature

∆f/fdt 20 Ta = −30 °C to +85 °C ⎯ 1* ⎯%

stability

Input offset voltage V

3, 4,

IO

FB1 = FB2 = 2 V ⎯ 15mV

8, 9 Input bias current I In-phase input

5-1. Error amplifier block [Error Amp1, Error Amp2]

voltage range Voltage gain A Frequency

bandwidth

Output voltage

Output source current

Output sink current I

* : Standard design value.

8

3, 4,

B

8, 9

3, 4,

V

CM

8, 9

5, 7 DC ⎯ 100* ⎯ dB

V

⎯ −100 −30 ⎯ nA

⎯ 0 ⎯ V

− 1.8 V

CC

BW 5, 7 AV = 0 dB ⎯ 2* ⎯ MHz

V

I

SOURCE

5, 7 ⎯ 4.7 4.9 ⎯ V

FBH

5, 7 ⎯⎯20 200 mV

FBL

5, 7 FB1 = FB2 = 2 V ⎯−2 −1mA

5, 7 FB1 = FB2 = 2 V 150 300 ⎯µA

SINK

(Continued)

Parameter

Sym-

bol

MB3887

(Ta = +25 °C, VCC = 19 V, VCC (O) = 19 V, VREF = 0 mA)

Pin No.

Conditions

Min Typ Max

Value

Unit

5-2. Error amplifier block [Error Amp3]

6. Current detection amplifier block [Current Amp1, Current Amp2]

V

Threshold voltage

V

Input current I Voltage gain A Frequency

bandwidth

BW 15 AV = 0 dB ⎯ 2* ⎯ MHz

V

Output voltage

V

Output source current

I

SOURCE

Output sink current I OUTD terminal

output leak current OUTD terminal

output ON resistor

I

R

Input offset voltage V

I

+INCH

I

−INCH

Input current

I

TH1

TH2

INE3

V

FBH

FBL

SINK

LEAK

ON

IO

+INCL

−INCL

16 FB3 = 2 V, Ta = +25 °C 4.183 4.200 4.225 V

FB3 = 2 V,

16

Ta = −10 °C to +85 °C

4.169 4.200 4.231 V

16 −INE3 = 0 V −100 −30 ⎯ nA

15 DC ⎯ 100* ⎯ dB

15 ⎯ 4.7 4.9 ⎯ V

15 ⎯⎯20 200 mV

15 FB3 = 2 V ⎯−2 −1mA

15 FB3 = 2 V 150 300 ⎯µA

11 OUTD = 17 V ⎯ 01µA

11 OUTD = 1 mA ⎯ 35 50 Ω

1,

+INC1 = +INC2 =

12,

−INC1 = −INC2 =

13,

3 V to VCC

24

+INC1 = +INC2 =

13,

3 V to VCC,

24

∆V

= −100 mV

IN

−3 ⎯+3mV

⎯ 20 30 µA

+INC1 = +INC2 =

1, 12

3 V to VCC,

⎯ 0.1 0.2 µA

∆Vin = −100 mV

13, 24+INC1 = +INC2 = 0 V,

∆Vin = −100 mV +INC1 = +INC2 = 0 V,

1, 12

∆Vin = −100 mV

−180 −120 ⎯µA

−195 −130 ⎯µA

* : Standard design value

(Continued)

9

MB3887

Parameter

6. Current detection amplifier block [Current Amp1, Current Amp2]

Sym-

bol

V

OUTC1

V

OUTC2

Current detection voltage

V

OUTC3

V

OUTC4

In-phase input voltage range

V

Voltage gain A

Frequency bandwidth

BW 2, 10 AV = 0 dB ⎯ 2* ⎯ MHz

V

OUTCH

Output voltage

V

(Ta = +25 °C, VCC = 19 V, VCC (O) = 19 V, VREF = 0 mA)

Pin No.

Conditions

Min Typ Max

Value

+INC1 = +INC2 =

2, 10

3 V to VCC,

1.9 2.0 2.1 V

∆Vin = −100 mV +INC1 = +INC2 =

2, 10

3 V to VCC,

0.34 0.40 0.46 V

∆Vin = −20 mV +INC1 = +INC2 =

2, 10

0 V to 3 V,

1.8 2.0 2.2 V

∆Vin = −100 mV +INC1 = +INC2 =

2, 10

0 V to 3 V,

0.2 0.4 0.6 V

∆Vin = −20 mV

1,

CM

12, 13,

⎯ 0 ⎯ V

24

+INC1 = +INC2 =

2, 10

V

3 V to VCC,

19 20 21 V/V

∆Vin = −100 mV

2, 10 ⎯ 4.7 4.9 ⎯ V 2, 10 ⎯⎯20 200 mV

OUTCL

CC

Unit

V

7. PWM comparator block [PWM Comp.]

* : Standard design value

10

Output source current

Output sink current

Threshold voltage

I

SOURCE

I

SINK

V

TL

TH

V

2, 10 OUTC1 = OUTC2 = 2 V ⎯−2 −1mA

2, 10 OUTC1 = OUTC2 = 2 V 150 300 ⎯µA

5, 7,

Duty cycle = 0 % 1.4 1.5 ⎯ V

15

5, 7,

Duty cycle = 100 %⎯2.5 2.6 V

15

(Continued)

Parameter

Sym-

bol

MB3887

(Ta = +25 °C, VCC = 19 V, VCC (O) = 19 V, VREF = 0 mA)

Pin No.

Conditions

Min Typ Max

Value

Unit

8. Output block [OUT]

9. Control block [CTL]

10. Bias voltage block [VH]

11. General

Output source current

Output sink current

Output ON resistor

I

SOURCE

I

SINK

R

OH

R

OL

20

20 20 OUT = −45 mA ⎯ 6.5 9.8 Ω

20 OUT = 45 mA ⎯ 5.0 7.5 Ω

Rise time tr1 20

Fall time tf1 20

14 IC Active mode 2 ⎯ 25 V

ON

V

CTL input voltage

V I

CTLH

14 IC Standby mode 0 ⎯ 0.8 V

OFF

14 CTL = 5 V ⎯ 100 150 µA

Input current

I

Output voltage V

Standby current I Power supply cur-

rent

CTLL

CCS

I

14 CTL = 0 V ⎯ 01µA

19

H

18

CC

OUT = 13 V, Duty ≤ 5 % (t = 1 / f

× Duty)

OSC

OUT = 19 V, Duty ≤ 5 % (t = 1 / f

× Duty)

OSC

OUT = 3300 pF (Si4435 × 1)

VCC = VCC (O) = 8 V to 25 V, VH = 0 to 30 mA

VCC = VCC (O) , CTL = 0 V

VCC = VCC (O) , CTL = 5 V

⎯−400* ⎯ mA

⎯ 400* ⎯ mA

⎯ 50* ⎯ ns

VCC − 6.5 VCC − 6.0 VCC − 5.5 V

⎯ 010µA

⎯ 812mA

* : Standard design value

11

Fujitsu MB3887 Schematic [ru]

DESCRIPTION

FEATURES

PACKAGE

PIN ASSIGNMENT

PIN DESCRIPTION

BLOCK DIAGRAM

ABSOLUTE MAXIMUM RATINGS

RECOMMENDED OPERATING CONDITIONS

ELECTRICAL CHARACTERISTICS