ROHM BD88400GUL, BD88410GUL, BD88415GUL, BD88420GUL Technical data

A

Headphone Amplifiers

Coupling Capacitorless
Headphone Amplifiers

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

No.11102EAT04

●Description

BD88xxxGUL is output coupling capacitorless headphone amplifier. This IC has a negative voltage generator of regulated
type built-in and generates the direct regulated negative voltage from the supply voltage. It is possible to drive headphones
in a ground standard with both voltage of the positive voltage (+2.4V) and the negative voltage (-2.4V). Therefore a
large-capacity output coupling capacitor becomes needless and can reduce a cost, a board area, and the height of the part.
In addition, there is not the signal decrement by the low range to happen by output coupling capacitor and output load
impedance and can output a rich low tone.

●Features

1) 2.4V to 5.5V Single-Supply Operation

2) No Bulky DC-Blocking Capacitors Required

3) No Degradation of Low-Frequency Response Due to Output Capacitors

4) Ground-Referenced Outputs

5) Gain setting
BD88400GUL: Variable gain with external resistors
BD88410GUL: -1.0V/V
BD88415GUL: -1.5V/V
BD88420GUL: -2.0V/V

6) Low THD+N

7) Low Supply Current

8) Integrated Negative Power Supply

9) Integrated Short-Circuit and Thermal-Overload Protection

10) Small package
VCSP50L2 (2.1mm x 2.1mm)

●Applications

Mobile Phones, Smart Phones, PDAs, Portable Audio Players, PCs, TVs, Digital Cameras, Digital Video Cameras,
Electronic Dictionaries, Voice Recorders, Bluetooth Head-sets, etc

●Line up

Supply

Type

BD88400GUL

BD88410GUL -1.0

BD88415GUL -1.5

BD88420GUL -2.0

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© 2011 ROHM Co., Ltd. All rights reserved.

Voltage

2.4～5.5

[V]

Supply

Current

[mA]

2.0

(No signal)

Gain
[V/V]

Variable gain
with external

resister

Maximum

Output Power

[mW]

(VDD=3.3V,RL=16Ω

THD+N≦1%,f=1kHz)

80

1/25

THD+N

[%]

0.006

(VDD=3.3V,RL=16Ω

Po=10mW,f=1kHz)

Noise
Voltage
[µVrms]

10

PSRR

[dB]

-80

(f=217Hz)

Package

VCSP50L2

(2.1mm x 2.1mm)

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

●Absolute maximum ratings

Parameter Symbol Ratings Unit

Technical Note

SGND to PGND voltage

SVDD to PVDD voltage

SVSS to PVSS voltage

SGND or PGND to SVDD, PVDD voltage

SVSS, PVSS to SGND or PGND voltage

SGND to IN_- voltage

SGND to OUT_- voltage

PGND to C1P- voltage

PGND to C1N- voltage

SGND to SHDN_B- voltage

Input current

Power Dissipation

Storage Temperature Range

* In operating over 25 ℃, de-rate the value to 10.8mW/℃. This value is for mounted on the application board
(Grass-epoxy, size: 40mm x 60mm, H=1.6mm, Top Copper area = 79.9%, Bottom Copper area = 80.2%).

VGG 0.0 V

VDD -0.3～0.3 V

VSS 0.0 V

VDG -0.3～6.0 V

VSG

-3.5～0.3

VIN (SVSS-0.3)～2.8 V

V

OUT

(PGND-0.3)～(PVDD+0.3) V

V

C1P

V

C1N

(SVSS-0.3)～2.8

(PVSS-0.3)～(PGND+0.3)

VSH (SGND-0.3)～(SVDD+0.3) V

IIN

-10～10

PD 1350 * mW

T

STG

-55～150 ℃

●Operating conditions

Parameter Symbol

Min. Typ. Max.

Ratings

V

V

V

mA

Unit

Supply Voltage Range

Operating Temperature Range

V

SVDD,VPVDD

T

OPR

2.4 - 5.5 V

-40 - +85 ℃

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2/25

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

●Electrical characteristics
Unless otherwise specified, Ta=25℃, SVDD=PVDD=3.3V, SGND=PGND=0V, SHDNB=SVDD, C1=C2=2.2µF,
RL=No Load, Ri=Rf=10kΩ

Parameter Symbol

Min. Typ. Max.

Limits

Unit Conditions

Supply Current

Shutdown Supply Current IST - 0.1 2 µA SHDNLB=SHDNRB=L

Technical Note

(SHDNLB,SHDNRB)=(H,L) or (L,H),
No signal

SHDNLB=SHDNRB=H,
No signal

Quiescent Supply Current

- 1.3 - mA

I

DD1

I

- 2.0 7.4 mA

DD2

SHDN_B Terminal

H Level Input Voltage VIH 1.95 - - V

L Level Input Voltage VIL - - 0.70 V

Input Leak Current I

- - ±1 µA

LEAK

Headphone Amplifier

Shutdown to Full Operation t

- 80 - µs SHDNLB=SHDNRB=L→H

SON

Offset Voltage VIS - ±0.5 ±5.0 mV

30 60 - mW

Maximum Output Power P

OUT

40 80 - mW

Total Harmonic Distortion
+ Noise

THD+N

- 0.008 0.056 %

- 0.006 0.100 %

Input Impedance ZIN 10 14 19 kΩ

RL=32Ω, THD+N≦-40dB, f=1kHz,
20kHz LPF, for Single Channel

RL=16Ω, THD+N≦-40dB, f=1kHz,
20kHz LPF, for Single Channel

RL=32Ω, POUT=10mW, f=1kHz,
20kHz LPF

RL=16Ω, POUT=10mW, f=1kHz,
20kHz LPF

SHDNLB=SHDNRB=H
In BD88400GUL, ZIN = Ri

Gain

BD88400GUL

BD88410GUL -1.05 -1.00 -0.95

AV

BD88415GUL -1.55 -1.50 -1.45

- -1.00 -

In BD88400GUL, Gain is variable

V/V

by the external resister of Ri and Rf.

BD88420GUL -2.06 -2.00 -1.94

Gain match ΔAV - 1 - %

Noise VN - 10 - µVrms 20kHz LPF + JIS-A

Slew Rate SR - 0.15 - V/µs

Maximum Capacitive Load CL - 200 - pF

Crosstalk CT - -90 - dB

Power Supply
Rejection Ratio

Charge-Pump
Oscillator Frequency

PSRR - -80 - dB

f

200 300 430 kHz

OSC

RL=32Ω, f=1kHz, VOUT=200mV
1kHz BPF

f=217Hz, 100mV

P-P

217Hz BPF

Thermal-Shutdown Threshold TSD - 145 - ℃

Thermal-Shutdown Hysteresis T

- 5 - ℃

HYS

‐ripple,

P-P

,

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© 2011 ROHM Co., Ltd. All rights reserved.

3/25

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

]

Technical Note

●Electrical characteristic curves – General Items (Reference data)
Unless otherwise specified, Ta=25℃, SGND=PGND=0V, SHDNLB=SHDNRB=SVDD, C1=C2=2.2µF,
Input coupling capacitor=1µF, RL=No Load

1u

SHDNLB=0V
SHDNRB=0V

100n

10n

* In BD88400GUL the input resister(Ri)=10kΩ, feedback resister(Rf)=10kΩ.

4.0

SHDNLB=VDD
SHDNRB=0V

* This caracteristics has

3.0

hyster esis (40mV typ) by
UVL O.

2.0

4.0

SHDNLB=VDD
SHDNRB=VDD

* This caracteristics has

3.0

hyster esis (40mV typ) by
UVL O.

2.0

Standby Current [A

1n

1.0

Operating Current [mA]

Operating Current [mA]

1.0

0.1n

0.0 1.0 2.0 3.0 4.0 5.0 6.0

Fig.1 Standby Current vs.

0

-0.5

-1

Supply V oltage [V]

Supply Voltage

SHDNLB=VDD
SHDNRB=VDD
No L oad

-1.5

-2

VSS Voltage [V]

-2.5

-3

2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0

Fig.4 Negative Voltage vs.

0

-10

-20

-30

-40

-50

-60

PSRR [dB]

-70

-80

-90

-100
10 100 1k 10k 100k

Fig.7 PSRR vs. Frequency

0

-10

-20

-30

-40

-50

-60

PSRR [dB]

-70

-80

-90

-100
10 100 1k 10k 100k

Supply V oltage [V]

Supply Voltage

VDD=2.4V
Ripple = 100mVp-p
BPF

Frequency [Hz]

(VDD=2.4V)

VDD=2.4V
VOUT = 200mVp-p
RL=32

Ω

BPF

Frequency [Hz]

Fig.10 Crosstalk vs.

© 2011 ROHM Co., Ltd. All rights reserved.

Frequency (VDD=2.4V)

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0.0

0.0 1.0 2.0 3.0 4.0 5.0 6.0

Supply V oltage [V]

Fig.2 Monaural Operating

Current vs. Supply Voltage

200

180

160

140

120

100

80

Setup time [us]

60

40

20

0

2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0

SHDNLB =SHDNRB
=L->H
VSS 90% Setup time
No Load

Supply V oltage [V]

Fig.5 Setup time vs.

Supply Voltage

0

VDD=3.3V

-10

Ripple = 100mVp-p

-20

BPF

-30

-40

-50

-60

PSRR [dB]

-70

-80

-90

-100
10 100 1k 10k 100k

Frequency [Hz]

Fig.8 PSRR vs. Frequency

(VDD=3.3V)

0

VDD=3.3V

-10

VOUT = 200mVp-p

-20

RL=32

-30

-40

-50

-60

PSRR [dB]

-70

-80

-90

-100
10 100 1k 10k 100k

Ω

BPF

Frequency [Hz]

Fig.11 Crosstalk vs.

Frequency (VDD=3.3V)

4/25

0.0

0.0 1.0 2.0 3.0 4.0 5.0 6.0

Supply V oltage [V]

Fig.3 Stereo Operating

Current vs. Supply voltage

120

100

80

60

40

20

Maximum Output Po wer [mW]

0

2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0

RL=16Ω, in phase

RL=16Ω, out of phase

RL=32Ω, in phase

RL=32Ω, out of phase

THD+N≦-40d B
20kHz LPF
Stereo

Supply V oltage [V]

Fig.6 Maximum power vs.

Supply Voltage

0

VDD=5.5V

-10

Ripple = 100mVp-p

-20

BPF

-30

-40

-50

-60

PSRR [dB]

-70

-80

-90

-100
10 100 1k 10k 100k

Fre quency [H z]

Fig.9 PSRR vs. Frequency

(VDD=5.5V)

0

VDD=5.5V

-10

VOUT = 200mVp-p

-20

RL=32

-30

-40

-50

-60

PSRR [dB]

-70

-80

-90

-100

Ω

BPF

10 100 1k 10k 100k

Frequency [Hz]

Fig.12 Crosstalk vs.

Frequency (VDD=5.5V)

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

●Electrical characteristic curves – BD88415GUL (Reference data)

0

-20

VDD=2.4V
f=1kHz
BPF

RL=32

VDD=3.3V

-20

0

f=1kHz
BPF

Ω

RL=32

Ω

-40

-60

-80

Output V olta ge [dBV]

-100

-120

-120 -100 -80 -60 -40 -20 0

Fig.13 Output Voltage vs.

Input Voltage (VDD=2.4V)

10

8

6

4

2

0

Gain [dB]

-2

-4

-6

-8

-10
10 100 1k 10k 100k

Fig.16 Gain vs. Frequency

Input Voltage [dBV]

VDD=2.4V
Po=10mW
RL=16

Ω

Input coupling
capacitor = 1.0uF

Frequency [Hz]

(VDD=2.4V)

RL=32

RL=16

RL=16

Ω

Ω

Ω

-40

-60

-80

Output V olta ge [dBV]

-100

-120

-120 -100 -80 -60 -40 -20 0

Input Voltage [dBV]

RL=16

Fig.14 Output Voltage vs.

Input Voltage (VDD=3.3V)

10

8

6

4

2

0

Gain [dB]

-2

VDD=3.3V
Po=10mW

-4

RL=16

-6

-8

-10
10 100 1k 10k 100k

Ω

Input coupling
capacitor = 1.0uF

Frequency [Hz]

RL=16

RL=32

Fig.17 Gain vs. Frequency

(VDD=3.3V)

Ω

Ω

Ω

100

100

10

10

1

0.1

THD+N [%]

VDD=2.4V
20kHz-LP F
f=1kHz

0.01

Stereo
RL=16

0.001
1n 100n 10u 1m 100m

Fig.19 THD+N vs. Output

Power (VDD=2.4V, RL=16Ω)

100

In p hase

Ω

Output P owe r [W]

Out of phase

1

0.1

THD+N [%]

VDD=3.3V
20kHz-LP F
f=1kHz

0.01

Stereo
RL=16

0.001
1n 100n 10u 1m 100m

In p hase

Ω

Output P owe r [W]

Out of phase

Fig.20 THD+N vs. Output

Power (VDD=3.3V, RL=16Ω)

100

10

1

0.1

THD+N [%]

VDD=2.4V
20kHz-LP F
f=1kHz

0.01

Stereo
RL=32

0.001
1n 100n 10u 1m 100m

In p hase

Ω

Output P ower [W]

Fig.22 THD+N vs. Output

Power (VDD=2.4V, RL=32Ω)

Out of phase

10

1

0.1

THD+N [%]

VDD=3.3V
20kHz-LP F
f=1kHz

0.01

Stereo
RL=32

0.001
1n 100n 10u 1m 100m

Ω

In p hase

Out of phase

Output P ower [W]

Fig.23 THD+N vs. Output

Power (VDD=3.3V, RL=32Ω)

Technical Note

VDD=5.5V

0

f=1kHz
BPF

-20

-40

-60

-80

Output V olta ge [dBV]

-100

-120

-120 -100 -80 -60 -40 -20 0

Fig.15 Output Voltage vs.

Input Voltage (VDD=5.5V)

10

8

6

4

2

0

Gain [dB]

-2

VDD=5.5V
Po=10mW

-4

RL=16

-6

-8

-10

Ω

Input coupling
capacitor = 1.0uF

10 100 1k 10k 100k

Fig.18 Gain vs. Frequency

(VDD=5.5V)

100

10

1

0.1

THD+N [%]

VDD=5.5V
20kHz-LP F
f=1kHz

0.01

Stereo
RL=16

0.001

Ω

1n 100n 10u 1m 100m

Fig.21 THD+N vs. Output

Power (VDD=5.5V, RL=16Ω)

100

10

1

0.1

THD+N [%]

VDD=5.5V
20kHz-LP F
f=1kHz

0.01

Stereo
RL=32

0.001

Ω

1n 100n 10u 1m 100m

Fig.24 THD+N vs. Output

Power (VDD=5.5V, RL=32Ω)

RL=32

RL=16

Input Voltage [dBV]

RL=16

RL=32

Frequency [Hz]

In p hase

Out of phase

Output P owe r [W]

In p hase

Out of phase

Output P ower [W]

Ω

Ω

Ω

Ω

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© 2011 ROHM Co., Ltd. All rights reserved.

5/25

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

●Electrical characteristic curves – BD88415GUL (Reference data) – Continued

100

10

1

0.1

THD+N [%]

VDD=2.4V
RL=16

Ω

20kHz-LP F
Stereo (in phase)

Po=1mW

Po=0.1mW

100

10

1

0.1

THD+N [%]

VDD=3.3V
RL=16Ω
20kHz-LPF
Ste reo (in phase )

Po=0.1mW

Po=1mW

0.01

0.001
10 100 1k 10k 100k

Fig.25 THD+N vs. Frequency

(VDD=2.4V, RL=16Ω)

Frequency [Hz]

Po=10mW

0.01

0.001
10 100 1k 10k 100k

Po=10mW

Frequency [Hz]

Fig. 26 THD+N vs. Frequency

(VDD=3.3V, RL=16Ω)

100

10

1

0.1

THD+N [%]

VDD=2.4V
RL=32

Ω

20kHz-LP F
Stereo (in phase)

Po=10mW

Po=0.1mW

100

10

1

0.1

THD+N [%]

VDD=3.3V
RL=32Ω
20kHz-LPF
Ste reo (in phase )

Po=0.1mW

Po=10mW

0.01

0.001
10 100 1k 10k 100k

Fig. 28 THD+N vs. Frequency

(VDD=2.4V, RL=32Ω)

Frequency [Hz]

Po=1mW

0.01

0.001
10 100 1k 10k 100k

Frequency [Hz]

Po=1mW

Fig. 29 THD+N vs. Frequency

(VDD=3.3V, RL=32Ω)

0

VDD=2.4V

-20

Input connect
to the ground

-40

with 1uF

-60

-80

Spectrum [dB V]

-100

-120

-140
10 100 1k 10k 100k

Frequency [Hz]

Fig.31 Noise Spectrum

(VDD=2.4V)

0

VDD=3.3V

-20

Input connect
to the ground

-40

with 1 uF

-60

-80

Spectrum [dBV]

-100

-120

-140
10 100 1k 10k 100k

Frequency [Hz]

Fig.32 Noise Spectrum

(VDD=3.3V)

Technical Note

100

VDD=5.5V
RL=16Ω

10

20kHz-LPF
Ste reo (in phase )

1

Po=1mW

0.1

THD+N [%]

0.01

0.001
10 100 1k 10k 100k

Fig. 27 THD+N vs. Frequency

(VDD=5.5V, RL=16Ω)

100

VDD=5.5V
RL=32Ω

10

20kHz-LPF
Ste reo (in phase )

1

Po=10mW

0.1

THD+N [%]

0.01

0.001
10 100 1k 10k 100k

Fig. 30 THD+N vs. Frequency

(VDD=5.5V, RL=32Ω)

0

VDD=5.5V

-20

Input connect
to the ground

-40

with 1 uF

-60

-80

Spectrum [dBV]

-100

-120

-140
10 100 1k 10k 100k

Fig.33 Noise Spectrum

(VDD=5.5V)

Po=0.1mW

Po=10mW

Frequency [Hz]

Po=0.1mW

Po=1mW

Frequency [Hz]

Frequency [Hz]

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© 2011 ROHM Co., Ltd. All rights reserved.

6/25

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

●Electrical characteristic curves – BD88400GUL (Reference data)

VDD=3.3V

0

f=1kHz
BPF

-20

-40

-60

-80

Output V olta ge [dBV]

-100

-120

-120 -100 -80 -60 -40 -20 0

Input Voltage [dBV]

Fig.34 Output Voltage vs.

Input Voltage (VDD=3.3V)

100

10

1

0.1

THD+N [%]

VDD=3.3V
20kHz-LP F
f=1kHz

0.01

Stereo
RL=32

0.001

Ω

1n 100n 10u 1m 100m

Output P owe r [W]

Fig. 37 THD+N vs. Output

Power (VDD=3.3V, RL=32Ω)

RL=32

Ω

RL=16

In p hase

Out of phase

Ω

10

VDD=3.3V, Po=10mW

8

Ri=10kΩ, Input co upling

6

capacitor = 1.0uF

4

2

0

Gain [dB]

-2

-4

-6

-8

-10
10 100 1k 10k 100k

Frequency [Hz]

RL=16

RL=32

Fig.35 Gain vs. Frequency

(VDD=3.3V)

100

VDD=3.3V
RL=16Ω

10

20kHz-LPF
Ste reo (in phase )

1

Po=1mW

0.1

THD+N [%]

0.01

0.001
10 100 1k 10k 100k

Po=0.1mW

Frequency [Hz]

Fig.38 THD+N vs. Frequency

(VDD=3.3V, RL=16Ω)

Ω

Ω

Po=10mW

0

VDD=3.3V

-20

Input connect
to the ground

-40

with 1uF

-60

-80

Spectrum [dBV]

-100

-120

-140
10 100 1k 10k 100k

Frequency [Hz]

Fig.40 Noise Spectrum

(VDD=3.3V)

Technical Note

100

10

1

0.1

THD+N [%]

VDD=3.3V
20kHz-LP F
f=1kHz

0.01

Stereo
RL=16

0.001

Ω

1n 100n 10u 1m 100m

Output P ower [W]

Fig.36 THD+N vs. Output

Power (VDD=3.3V, RL=16Ω)

100

VDD=3.3V
RL=32Ω

10

20kHz-LPF
Ste reo (in phase )

1

Po=1mW

0.1

THD+N [%]

0.01

0.001
10 100 1k 10k 100k

Fig. 39 THD+N vs. Frequency

(VDD=3.3V, RL=32Ω)

In p hase

Out o f p hase

Po=0.1mW

Po=10mW

Frequency [Hz]

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© 2011 ROHM Co., Ltd. All rights reserved.

7/25

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

●Electrical characteristic curves – BD88410GUL (Reference data)

VDD=3.3V

0

f=1kHz
BPF

-20

-40

-60

-80

Output V olta ge [dBV]

-100

-120

-120 -100 -80 -60 -40 -20 0

RL=32

Input Voltage [dBV]

Fig.41 Output Voltage vs.

Input Voltage (VDD=3.3V)

100

10

1

In p hase

0.1

THD+N [%]

VDD=3.3V
20kHz-LP F
f=1kHz

0.01

Stereo
RL=32

0.001

Ω

1n 100n 10u 1m 100m

Output P ower [W]

Fig. 44 THD+N vs. Output

Power (VDD=3.3V, RL=32Ω)

Ω

RL=16

Ω

Out o f p hase

10

VDD=3.3V

8

Po=10mW

6

Input coupling

4

capacitor = 1.0uF

2

0

Gain [dB]

-2

-4

-6

-8

-10
10 100 1k 10k 100k

Frequency [Hz]

RL=16

RL=32

Fig.42 Gain vs. Frequency

(VDD=3.3V)

100

VDD=3.3V
RL=16Ω

10

20kHz-LPF
Ste reo (in phase )

1

Po=1mW

0.1

THD+N [%]

0.01

0.001
10 100 1k 10k 100k

Po=0.1mW

Po=10mW

Frequency [Hz]

Fig.45 THD+N vs. Frequency

(VDD=3.3V, RL=16Ω)

Ω

Ω

0

VDD=3.3V

-20

Input connect
to the ground

-40

with 1uF

-60

-80

Spectrum [dBV]

-100

-120

-140
10 100 1k 10k 100k

Frequency [Hz]

Fig.47 Noise Spectrum

(VDD=3.3V)

Technical Note

100

10

1

0.1

THD+N [%]

VDD=3.3V
20kHz-LP F
f=1kHz

0.01

Stereo
RL=16

0.001

Ω

1n 100n 10u 1m 100m

Output P ower [W]

Fig.43 THD+N vs. Output

Power (VDD=3.3V, RL=16Ω)

100

VDD=3.3V
RL=32Ω

10

20kHz-LPF
Ste reo (in phase )

1

Po=1mW

0.1

THD+N [%]

0.01

0.001
10 100 1k 10k 100k

Fig. 46 THD+N vs. Frequency

(VDD=3.3V, RL=32Ω)

In p hase

Out o f p hase

Po=0.1mW

Po=10mW

Frequency [Hz]

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8/25

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

●Electrical characteristic curves – BD88420GUL (Reference data)

VDD=3.3V

0

f=1kHz
BPF

-20

-40

-60

-80

Output Voltage [dBV]

-100

-120

-120 -100 -80 -60 -40 -20 0

RL=32

Input Voltage [dBV]

Fig.48 Output Voltage vs.

Input Voltage (VDD=3.3V)

100

10

1

0.1

THD+N [%]

VDD=3.3V
20kHz-LP F
f=1kHz

0.01

Stereo
RL=32

0.001

Ω

1n 100n 10u 1m 100m

Output P ower [W]

Fig. 51 THD+N vs. Output

Power (VDD=3.3V, RL=32Ω)

Ω

RL=16

In p hase

Out o f p hase

Ω

10

8

6

4

2

0

Gain [dB]

-2

VDD=3.3V

-4

Po=10mW

-6

Input coupling

-8

capacitor = 1.0uF

-10
10 100 1k 10k 100k

Frequency [Hz]

RL=16

RL=32

Fig.49 Gain vs. Frequency

(VDD=3.3V)

100

VDD=3.3V
RL=16Ω

10

20kHz-LPF
Ste reo (in phase )

1

Po=1mW

0.1

THD+N [%]

0.01

0.001
10 100 1k 10k 100k

Po=0.1mW

Po=10mW

Frequency [Hz]

Fig.52 THD+N vs. Frequency

(VDD=3.3V, RL=16Ω)

Ω

Ω

0

VDD=3.3V

-20

Input connect
to the ground

-40

with 1uF

-60

-80

Spectrum [dBV]

-100

-120

-140
10 100 1k 10k 100k

Frequency [Hz]

Fig.54 Noise Spectrum

(VDD=3.3V)

Technical Note

100

10

1

0.1

THD+N [%]

VDD=3.3V
20kHz-LP F
f=1kHz

0.01

Stereo
RL=16

0.001

Ω

1n 100n 10u 1m 100m

Fig.50 THD+N vs. Output

Power (VDD=3.3V, RL=16Ω)

100

VDD=3.3V
RL=32Ω

10

20kHz-LPF
Ste reo (in phase )

1

Po=1mW

0.1

THD+N [%]

0.01

0.001
10 100 1k 10k 100k

Fig. 53 THD+N vs. Frequency

(VDD=3.3V, RL=32Ω)

In p hase

Out o f p hase

Output P ower [W]

Po=0.1mW

Po=10mW

Frequency [Hz]

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© 2011 ROHM Co., Ltd. All rights reserved.

9/25

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

●Pin Arrangement

1 2 3 4

D SVDD OUTL SVSS PVSS

C INL OUTR C1N
B SHDNRB SHDNLB PGND

A INR SGND PVDD C1P

(Bottom View)

●Pin Function

Ball

Matrix

Pin name Function Symbol

A1 INR Headphone Amplifier (Rch) input C

A2 SGND Ground for Headphone Amplifier -

A3 PVDD Positive Power Supply for Charge Pump -

A4 C1P Flying Capacitor (CF) Positive A

B1 SHDNRB Headphone Amplifier (Rch) Shutdown Control (H:active, L:shutdown) E

B2 SHDNLB Headphone Amplifier (Lch) Shutdown Control (H:active, L:shutdown) E

B4 PGND Ground for Charge Pump -

C1 INL Headphone Amplifier (Lch) input C

C2 OUTR Headphone Amplifier (Rch) output D

C4 C1N Flying Capacitor (CF) Negative B

D1 SVDD Ground for Headphone Amplifier -

D2 OUTL Headphone Amplifier (Lch) output D

D3 SVSS Negative Supply Voltage for Signal -

D4 PVSS Negative Supply Voltage output F

●Pin equivalent circuit

PVDD PVDD

PGND PGND

PAD

A

PGND PGND

B

PVSS PVSS

SVDD

SVDD

-

+

D

SVSS

PAD

E

SGND

Fig.55 Pin equivalent circuit

PAD

PAD

Technical Note

SVDD

-

+

C

SVSS

PGND

F

PAD

PGND

PAD

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10/25

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

●Block Diagram

SHDNRB

SHDNLB

B2B1

C1

PVDD

A3

C1P

A4

SVDD

PGND

B4

CHARGE

PUMP

UVLO/

SHUTDOW N

CONTROL

C1N

PVSS

C4

D4

PVDD

CHARGE

PUMP

CONTROL

SVDD

CLOCK

GENERATOR

SGND

A2

SGND

A1

INR INL

Type Rin Rfb

Rin

SVDD

TSD

SGND

SGND

Rfb

SVDD

-

+

SVSS

PROTECTION

SVSS

+

-

SVDD

RfbRin

SVDD

SHORT

SVSS

Technical Note

SVDD

D1

OUTL

D2

OUTR

C2

SVSS

D3

BD88400GUL 14kΩ

BD88410GUL 14kΩ

BD88415GUL 14kΩ

BD88420GUL 14kΩ

Open

@Typ.

14kΩ

@Typ.

21kΩ

@Typ.

28kΩ

@Typ.

@Typ.

@Typ.

@Typ.

Fig.56 Block Diagram

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11/25

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

Technical Note

●Functional descriptions

The conventional headphone amplifier composition is occupied to Fig.57. In this composition, the signal is output by using
the middle point bias circuit based on the middle point bias. Therefore, the output coupling capacitor that removes the DC
voltage difference and does the AC coupling is necessary. This coupling capacitor and the impedance of the headphone
composes the high-pass filter. Therefore, the signal degradation in the low frequency region learns by experience. The
output coupling capacitor should be a large capacity, because the cutoff frequency of this high-pass filter becomes the
following formula (1).

fπ (1)

c

* Cc is the coupling capacitor, and RL is the impedance of the headphone.

1

CR2

CL

Moreover, POP noise by the middle point bias start-up is generated and the degradation of PSRR learns by experience.

Vout

Input

VDD

-

Cc

+

Vhp

Vout [V]

VDD

VDD/2

+

GND

Middle Point
Bias Circu it

0

tim e [s]

Vhp [V]

0

tim e [s]

Fig.57 Conventional headphone amplifier composition

The composition of the series of BD884xxGUL is occupied to Fig.58. In this composition, the signal is output by using a
negative voltage based on the ground level. Therefore, the amplifier output can be connected directly with the headphone.
And, the output coupling capacitor becomes unnecessary. Additionally, the signal degradation in the low frequency region
with the coupling capacitor is not generated, and the deep bass is achieved.
Moreover, POP noise is controlled because of no middle point bias start-up. And, the degradation of PSRR doesn't occur by
being based on the ground.

Input

Vout

HPVDD

­+

CF : Flying

Capacitor

Charge

Pump

Vhp

VDD

HPVDD

Vout [V]

0

time [s]

VSS

CH : Hold
Capacitor

Vhp [V]

0

time [s]

Fig.58 Composition of the series of BD884xxGUL

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12/25

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

]

]

Technical Note

[CHARGE PUMP / CHARGE PUMP CONTROL]
The negative power supply circuit is composed of the regulated charge-pump. This circuit outputs the regulated negative
voltage (PVSS) directly from power-supply voltage (PVDD). Therefore, it doesn't depend on the power-supply voltage, and
a constant voltage is output (PVSS=-2.4V

, refer to Fig.4). Moreover, there is not swinging of the power supply by the

@Typ.

output current of the headphone amplifier, and it doesn't influence the headphone amplifier characteristic.

0

Ta=25
VDD=3.3V

-0.5

SHDN_B=SVDD
CF=CH=2.2uF

-1

-1.5

℃

VSS Voltage [V]

-2

-2.5

-3
0 20406080

Load Current [mA]

Fig.59 Characteristics of load current regulation of PVSS (Reference data)

・Power control

The power control is a logical sum of SHDNLB and SHDNRB. The negative power supply circuit starts when H level is
input to either of SHDNLB or SHDNRB, and power is downed at the SHDNLB=SHDNRB=L level.

Table.1 Control of the charge pump

SHDNLB SHDNRB Control

L L Power down

L H Power on

H L Power on

H H Power on

・Operating Frequency

The operating frequency of the negative power supply charge pump is designed for the temperature and the voltage
dependence may decrease. The reference data (measurements) is occupied to Fig.60. Please note the interference with
the frequency in the application board.

400

VDD=3.3V

380

Measure : C1P

360

CF=CH=2.2uF

340

320

300

280

260

240

220

Charge Pum p Ocs illator Frequency [kHz

200

-50.0 0.0 50.0 100.0

Ta [℃]

400

Ta=25

380

360

340

320

300

280

260

240

220

Charge Pum p Ocs illator Frequency [kHz

200

2.0 3.0 4.0 5.0 6.0

℃

Measure : C1P
CF=CH=2.2uF

Supply Voltage[V]

Fig.60 Temperature characteristic and Voltage characteristic of operating frequency (Reference data)

・The flying capacitor and the hold capacitor

The flying capacitor (CF) and the hold capacitor (CH) greatly influence the characteristic of the charge pump. Therefore,
please connect the capacitor with an excellent temperature characteristic and voltage characteristic of 2.2µF as much as
possible near IC.

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© 2011 ROHM Co., Ltd. All rights reserved.

13/25

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

Technical Note

[HEADPHONE AMP]
The headphone amplifier is driven by the internal positive voltage (+2.4V) and negative voltage (SVSS, -2.4V) based on
ground (SGND). Therefore, the headphone can be connected without the output coupling capacitor. As a result, it brings the
improved low-frequency characteristic compared with the headphone of the conventional coupling capacitor type.

・Power control

L channel and R channel of the headphone amplifier can be independently controlled by SHDNLB and SHDNRB logic.
When the SVSS voltage is -1.1V

or more, the headphone amplifier does not operate to protect from illegal operation.

@Typ.

And in addition, the overcurrent protection circuit is built in. The amplifier is shutdown when the overcurrent occurs
because of the output short-circuit etc., and IC is protected from being destroyed.

Table.2 Control of the headphone amplifier

SHDNLB SHDNRB L channel R channel

L L Power down Power down

L H Power down Power on

H L Power on Power down

H H Power on Power on

[V]

VDD

SHDNx B

[V]

-1.1V

0

0

Amprilier

Disable

SVSS

Amplifier

En a b le

[time]

[time]

Fig.61 Area of headphone amplifier can operate

SVSS does not have internal connection with PVSS. Please connect SVSS with PVSS on the application board.

・Input coupling capacitor

Input DC level of BD884xxGUL is 0V (SGND). The input coupling capacitor is necessary for the connection with the
signal source device. The signal decrease happens in the low frequency because of composing the high-pass filter by
this input coupling capacitor and the input impedance of BD884xxGUL.
The input impedance of BD884xxGUL is Rin (14kΩ

). The cutoff frequency of this high-pass filter becomes the

@Typ.

following formula. (In BD88400GUL, Rin becomes external resistance Ri. )

f  (2)

c

1

CRπ2

* Cin is the input coupling capacitor.

inin

9.0

6.0

3.0

0.0

-3.0

-6.0

Gain [dB]

-9.0

-12.0

-15.0

-18.0

-21.0
1 10 100

Rin=14k

Cin=10uF

Cin=1uF

Ω

Cin=4.7uF

Cin=2.2uF

Frequency [Hz]

Fig.62 Frequency response by the input coupling capacitor (Reference data)

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14/25

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

Technical Note

And, the degradation of THD+N happens because of the input coupling capacitor. Therefore, please consider these about
the selection of parts.

0

-10

-20

Cin=1.0uF

-30

-40

-50

-60

THD+N [dB]

-70

-80

-90

-100

Cin=0.47uF

10 100 1k 10k 100k

BD88415GUL
VDD=3.3V
Po=10mW
RL=16
20kHz LPF

Cin=0.22uF

Cin=2.2uF

Frequency [Hz]

Ω

* Capacitor size: 1608

Fig.63 THD+N by the input coupling capacitor (Reference data)

・State of terminal when power down

The state of the terminal changes by the power control of the headphone amplifier. When it is shutdown, the input
impedance of the input terminal becomes 7.1kΩ

(In BD88400GUL, become Ri + 7.1kΩ). The time constant can be

@Typ.

reduced when the input coupling capacitor is charged.
The input voltage changes while charging up the input coupling capacitor. Therefore, do not operate the headphone
amplifier while charging.

Audio

Source

Vs Vin

Ci n

Rin =7.1kΩ

Vout

VDD

-

+

VSS

Vs [V]

0

Vin [V]

0

Output

Bias

tim e [s]

Output

Bias

tim e [s]

Fig.64 Input voltage transition with input coupling capacitor

This charge time constant becomes the following formula (3) by using the input coupling capacitor and the input
impedance. And the calculation value of the convergence to the wait time is indicated in Fig.65.

CRτ  (3)

inin

* Rin=7.1kΩ

. In BD88400GUL, Rin=Ri+7.1kΩ

@Typ.

100

90
80
70
60
50
40
30

Convergence [%]

20
10

0

0τ 1τ 2τ 3τ 4τ 5τ 6τ 7τ 8τ

Wait ti me [s]

Fig.65 Wait time and convergence (Reference)

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© 2011 ROHM Co., Ltd. All rights reserved.

15/25

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

Technical Note

[UVLO / SHUTDOWN CONTROL]
BD884xxGUL has low voltage protection function (UVLO: Under Voltage Lock Out). And protect from the illegal operation of
IC by a low power supply voltage.
The detection voltage is 2.13V

, so it does not influence 2.4V of recommended operation voltage. UVLO controls the

@Typ.

whole of IC, and does both the negative power supply charge pump and the headphone amplifier in power down.

[TSD]
BD884xxGUL has overheating protection function (TSD: Thermal Shutdown). And the headphone amplifier becomes
shutdown when illegally overheating by the headphone amplifier illegally operation.

●Timming Chart

(Usually Operation)

PVDD,SV DD

SHDNLB

SHDNRB

Amp enable

PVSS,SVSS

(UVLO Operation)

(TSD Operation)

INL,INR

OUTL

OUTR

Shutdow n Setup Signal output Shutdow n

Fig.66 Usually Operation

PVDD,SVDD

SHDNLB,
SHDNRB

PVSS,SVSS

OUTL

OUTR

SetupSignal output Signal outputUVLO

Fig.67 UVLO Operation

Hy steresis = 5℃

Ta

PV DD ,S V DD

SHDNL B,

SHDNRB

PVSS,SVSS

OUTL

OUTR

Signal output Signal outputTSD

Fig.68 TSD Operation

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16/25

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

Technical Note

●Application Circuit

3.3V

PVDD

A3

Cpvdd

1.0μF

C1P

A4

PGND

CF

2.2μF

CH

2.2μF

CHARGE

B4

C1N

C4

PVSS

D4

PUMP

CHARGE

PUMP

CONTROL

SHUTDOWN

SHUTDOWN

PVDD

SGND

A2

Control

UVLO/

CONTROL

CLOCK

GENERATOR

Lch Input

Cil

1.0μF

C1

B2B1

Rfb

Rin

SVDD

-

+

SVDD

SVSS

SGND

SGND

SVSS

SVDD

PROTECTION

+

-

Rfb

SHORT

TSD

Rin

SVDD

SVDD

A1

Rch Input

1.0μF

Cir

SVDD

SVSS

3.3V

SVDD

D1

Csvdd

1.0μF

OUTL

D2

OUTR

C2

SVSS

D3

Part Function value Remarks

CF

CH

Cpvdd

Csvdd

Cil

Cir

Flying
Capacitor
Hold
Capacitor
Bypass
Capacitor
Bypass
Capacitor
Coupling
Capacitor
Coupling
Capacitor

2.2µF

2.2µF

1.0µF

1.0µF

1.0µF

1.0µF

Temp. Characteristic：
Class-B
Temp. Characteristic：
Class-B
Temp. Characteristic：
Class-B
Temp. Characteristic：
Class-B
Temp. Characteristic：
Class-B
Temp. Characteristic：
Class-B

Fig.69 BD88410GU/BD88415GUL/BD88420GUL application circuit

SHDNLB

SHDNRB

Part Function value Remarks

CF

CH

Cpvdd

Csvdd

Cil

Cir

Ri

Rf

Flying
Capacitor
Hold
Capacitor
Bypass
Capacitor
Bypass
Capacitor
Coupling
Capacitor
Coupling
Capacitor
Input
Resistor
Feedback
Resistor

2.2µF

2.2µF

1.0µF

1.0µF

1.0µF

1.0µF

10kΩ

10kΩ

Temp. Characteristic：
Class-B
Temp. Characteristic：
Class-B
Temp. Characteristic：
Class-B
Temp. Characteristic：
Class-B
Temp. Characteristic：
Class-B
Temp. Characteristic：
Class-B
MCR006YZPJ103
(ROHM)
MCR006YZPJ103
(ROHM)

SGND

INR INL

Fig.70 BD88400GUL application circuit

In BD88400GUL, the Pass Gain becomes the following formula (4). The Pass Gain and the resister Rf is limited by table.3.

R

Gain  (4)

f

R

i

Table.3 Pass Gain and Resister Limit

Item Min. Typ. Max. Unit

Pass Gain 0.5 1.0 2.0 V/V

Rf 1.0 10 - kΩ
Ri - 10 - kΩ

Ri is not limited. But, if this resister Ri is very small, the signal decrease happens in the low frequency (Refer to formula 2).

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17/25

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

●Thermal Derating Curve

The reference value of the thermal derating curve is indicated in Fig.71.

(Conditions)
This value is for mounted on the ROHM application board
Board size：40mm x 60mm x 1.6mm

Top Copper Area：79.9%
Bottom Copper Area：80.2%
Board Layout：Fig.74

1.6

1.4

1.2

1

0.8

Pd [W]

0.6

0.4

0.2

0

0 25 50 75 100 125 150

Ta [℃]

Fig.71 Thermal Derating Curve

Technical Note

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© 2011 ROHM Co., Ltd. All rights reserved.

18/25

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

Technical Note

●Evaluation Board

D8876FV Evaluation Board loads with the necessary parts. It can operate only by it. It is using RCA Connector for input
terminal and Headphone jack (φ=3.5mm) for output terminal. Therefore it can easily connect between Audio equipments.
And it can operate by single supply (2.4 to 5.5V). The switch on the board (SDB) can control shutdown.

(Spec.)

Item Limit Unit

Supply Voltage Range (VDD) 3.0 to 5.5 V

Maximum Supply Current 1.0 A
Operating Temperature Range -40 to 85 ℃

Input Voltage Range -2.5 to 2.5 V

Output Voltage Range -2.5 to 2.5 V
Minimum Load Impedance 15 Ω

(Schematic)

OUTL OUTR

CN1

Headphone

Jack

IN<L>

RCA(White )

VDD

3.3V

+

GND

GND

(Open)

R

L

IN<L>

C6

1μF

A3

C7
10uF

VDD

C2

1μF

SHDNLB SHDNRB

SW2 SW1

C5

1μF

B4

A2

R5R6

D2 C2

C1

OUTL

INL

OUTR

INR

BD88410GUL
/ BD88415GUL
/ BD88420GUL

PVDD

D1

SVDD

PGND

SGND

B2

SHDNLB

C1P

C1N

PVSS

SVSS

SHDNRB

A1

A4

C4

D4

D3

B1

C1

2.2μF

C3

2.2μF

C4

1μF

GND

IN<R>

IN<R>

RCA(Red)

VSS

VDD

(Open)

GND

GND

Fig.72 Evaluation Board Schematic (BD88410GUL/BD88415GUL/BD88420GUL)

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19/25

2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

A

OUTL OUTR

Technical Note

CN1

Headphone

Jack

IN<L>

RCA(White )

VDD

3.3V

+

GND

GND

(Open)

R

L

R4
10kΩ

IN<L>

C6

R3

1μF

10kΩ

A3

C7
10uF

VDD

C2

1μF

SHDNLB SHDNRB

SW2 SW1

C5

1μF

B4

A2

R5R6

D2 C2

C1

D1

B2

OUTL

INL

BD88400GUL

PVDD

SVDD

PGND

SGND

SHDNLB

OUTR

INR

C1P

C1N

PVSS

SVSS

SHDNRB

A1

A4

C4

D4

D3

B1

R2
10kΩ

R1

10kΩ

C1

2.2μF

C3

2.2μF

C4

1μF

GND

IN<R>

IN<R>

RCA(Red)

VSS

VDD

(Open)

GND

GND

Fig.73 Evaluation Board Schematic (BD88400GUL)

(Parts List)

Parts name Type Value Size

U1 CSP-14pin BD884xxGUL 2.1mm x 2.1mm

C1, C3 Chip Ceramic capacitor 2.2µF 1608

C2, C4～C6 Chip Ceramic capacitor 1.0µF 1608

C7 Tantalum capacitor 10µF 3216

R1～R4 Chip Resistor 10kΩ 1608

R5, R6 Chip Resistor Open -

CN1 Headphone jack - φ=3.5mm

R1～R4 * Chip Resistor 10kΩ 1608

*About BD88200GUL, R1～R4 of is the resistor for the gain setting.

(Operation procedure)

① Turn off the switch (SHNDLB/SHDNRB) on evaluation board.
② Connect the positive terminal of the power supply to the VDD pin and ground terminal to the GND pin.
③ Connect the left output of the audio source to the INL and connect the right output to the INR.
④ Turn on the power supply.
⑤ Turn on the switch (SHDNLB/SHDNRB) on the evaluation board. (H)
⑥ Input the audio source.

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2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

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(Board Layout)

(TOP SILKSCREEN – TOP VIEW) (TOP LAYER - TOP VIEW)

(BOTTOM LAYER – TOP VIEW) (BOTTOM SILKSCREEN – TOP VIEW)

Fig.74 ROHM Application Board Layout (BD88410GUL/BD88415GUL/BD88420GUL)

Technical Note

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2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

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(TOP SILKSCREEN – TOP VIEW) (TOP LAYER - TOP VIEW)

(BOTTOM LAYER – TOP VIEW) (BOTTOM SILKSCREEN – TOP VIEW)

Fig.75 ROHM Application Board Layout (BD88400GUL)

Technical Note

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2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

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●Notes for use

(1) Absolute Maximum Ratings

An excess in the absolute maximum ratings, such as supply voltage, temperature range of operating conditions, etc.,
can break down devices, thus making impossible to identify breaking mode such as a short circuit or an open circuit. If
any special mode exceeding the absolute maximum ratings is assumed, consideration should be given to take physical
safety measures including the use of fuses, etc.

(2) Operating conditions

These conditions represent a range within which characteristics can be provided approximately as expected. The
electrical characteristics are guaranteed under the conditions of each parameter.

(3) Reverse connection of power supply connector

The reverse connection of power supply connector can break down ICs. Take protective measures against the
breakdown due to the reverse connection, such as mounting an external diode between the power supply and the IC’s
power supply terminal.

(4) Power supply line

Design PCB pattern to provide low impedance for the wiring between the power supply and the GND lines. In this
regard, for the digital block power supply and the analog block power supply, even though these power supplies has
the same level of potential, separate the power supply pattern for the digital block from that for the analog block, thus
suppressing the diffraction of digital noises to the analog block power supply resulting from impedance common to the
wiring patterns. For the GND line, give consideration to design the patterns in a similar manner.
Furthermore, for all power supply terminals to ICs, mount a capacitor between the power supply and the GND terminal.
At the same time, in order to use an electrolytic capacitor, thoroughly check to be sure the characteristics of the
capacitor to be used present no problem including the occurrence of capacity dropout at a low temperature, thus
determining the constant.

(5) GND voltage

Make setting of the potential of the GND terminal so that it will be maintained at the minimum in any operating state.
Furthermore, check to be sure no terminals are at a potential lower than the GND voltage including an actual electric
transient.

(6) Short circuit between terminals and erroneous mounting

In order to mount ICs on a set PCB, pay thorough attention to the direction and offset of the ICs. Erroneous mounting
can break down the ICs. Furthermore, if a short circuit occurs due to foreign matters entering between terminals or
between the terminal and the power supply or the GND terminal, the ICs can break down.

(7) Operation in strong electromagnetic field

Be noted that using ICs in the strong electromagnetic field can malfunction them.

(8) Inspection with set PCB

On the inspection with the set PCB, if a capacitor is connected to a low-impedance IC terminal, the IC can suffer stress.
Therefore, be sure to discharge from the set PCB by each process. Furthermore, in order to mount or dismount the set
PCB to/from the jig for the inspection process, be sure to turn OFF the power supply and then mount the set PCB to
the jig. After the completion of the inspection, be sure to turn OFF the power supply and then dismount it from the jig. In
addition, for protection against static electricity, establish a ground for the assembly process and pay thorough attention
to the transportation and the storage of the set PCB.

(9) Input terminals

In terms of the construction of IC, parasitic elements are inevitably formed in relation to potential. The operation of the
parasitic element can cause interference with circuit operation, thus resulting in a malfunction and then breakdown of
the input terminal. Therefore, pay thorough attention not to handle the input terminals, such as to apply to the input
terminals a voltage lower than the GND respectively, so that any parasitic element will operate. Furthermore, do not
apply a voltage to the input terminals when no power supply voltage is applied to the IC. In addition, even if the power
supply voltage is applied, apply to the input terminals a voltage lower than the power supply voltage or within the
guaranteed value of electrical characteristics.

(10) Ground wiring pattern

If small-signal GND and large-current GND are provided, It will be recommended to separate the large-current GND
pattern from the small-signal GND pattern and establish a single ground at the reference point of the set PCB so that
resistance to the wiring pattern and voltage fluctuations due to a large current will cause no fluctuations in voltages of
the small-signal GND. Pay attention not to cause fluctuations in the GND wiring pattern of external parts as well.

(11) External capacitor

In order to use a ceramic capacitor as the external capacitor, determine the constant with consideration given to a
degradation in the nominal capacitance due to DC bias and changes in the capacitance due to temperature, etc.

(12) About the rush current

For ICs with more than one power supply, it is possible that rush current may flow instantaneously due to the internal
powering sequence and delays. Therefore, give special consideration to power coupling capacitance, power wiring,
width of GND wiring, and routing of wiring.

Technical Note

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2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

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●Ordering part number

B D 8 8 4 1 5 G U L - E 2

Part No. Part No.

VCSP50L2

(BD88400GUL)

1PIN MARK

14-φ0.25±0.05

0.05

BA

(φ0.15)INDEX POST

0.30±0.05

VCSP50L2

(BD88410GUL)

1PIN MARK

14-φ0.25±0.05

0.05

BA

(φ0.15)INDEX POST

0.30±0.05

VCSP50L2

(BD88415GUL)

1PIN MARK

14-φ0.25±0.05

0.05

BA

(φ0.15)INDEX POST

0.30±0.05

BD88400
BD88410
BD88415
BD88420

2.10±0.05

0.06 S

A

D
C
B
A

3

2

1

P=0.5×3

2.10±0.05

0.06 S

A

D
C
B
A

3

2

1

P=0.5×3

2.10±0.05

0.06 S

A

D
C
B
A

3

2

1

P=0.5×3

<Tape and Reel information>

2.10±0.05

0.55MAX

0.1±0.05

S

0.30±0.05

B

P=0.5×3

4

(Unit : mm)

<Tape and Reel information>

2.10±0.05

0.55MAX

0.1±0.05

S

0.30±0.05

B

P=0.5×3

4

(Unit : mm)

<Tape and Reel information>

2.10±0.05

0.55MAX

0.1±0.05

S

0.30±0.05

B

P=0.5×3

4

(Unit : mm)

Package
GUL: VCSP50L2

Embossed carrier tapeTape

Quantity

Direction
of feed

Quantity

Direction
of feed

Quantity

Direction
of feed

3000pcs
E2

()

Reel

Embossed carrier tapeTape
3000pcs

E2

()

Reel

Reel

Packaging and formingspecification
E2: Embossed tape and reel

The direction is the 1pin of product is at the upper left when you hold
reel on the left hand and you pull out the tape on the right hand

1pin

Order quantity needs to be multiple of the minimum quantity.

∗

The direction is the 1pin of product is at the upper left when you hold
reel on the left hand and you pull out the tape on the right hand

1pin

Order quantity needs to be multiple of the minimum quantity.

∗

Embossed carrier tapeTape
3000pcs

E2

The direction is the 1pin of product is at the upper left when you hold

()

reel on the left hand and you pull out the tape on the right hand

1pin

Order quantity needs to be multiple of the minimum quantity.

∗

Direction of feed

Direction of feed

Direction of feed

Technical Note

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2011.03 – Rev.

BD88400GUL,BD88410GUL,BD88415GUL,BD88420GUL

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VCSP50L2

(BD88420GUL)

1PIN MARK

14-φ0.25±0.05

0.05

BA

(φ0.15)INDEX POST

0.30±0.05

D
C
B
A

2.10±0.05

2

1

P=0.5×3

0.06 S

3

<Tape and Reel information>

Embossed carrier tapeTape

Quantity

2.10±0.05

0.55MAX

0.1±0.05

S

A

0.30±0.05

B

P=0.5×3

4

(Unit : mm)

Direction
of feed

3000pcs
E2

The direction is the 1pin of product is at the upper left when you hold

()

reel on the left hand and you pull out the tape on the right hand

Reel

Technical Note

1pin

Order quantity needs to be multiple of the minimum quantity.

∗

Direction of feed

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25/25

2011.03 – Rev.

Notes

No copying or reproduction of this document, in par t or in whole, is permitted without the
consent of ROHM Co.,Ltd.

The content specied herein is subject to change for improvement without notice.

The content specied herein is for the purpose of introducing ROHM's products (hereinafter
"Products"). If you wish to use any such Product, please be sure to refer to the specications,
which can be obtained from ROHM upon request.

Examples of application circuits, circuit constants and any other information contained herein
illustrate the standard usage and operations of the Products. The peripheral conditions must
be taken into account when designing circuits for mass production.

Great care was taken in ensuring the accuracy of the information specied in this document.
However, should you incur any damage arising from any inaccuracy or misprint of such
information, ROHM shall bear no responsibility for such damage.

The technical information specied herein is intended only to show the typical functions of and
examples of application circuits for the Products. ROHM does not grant you, explicitly or
implicitly, any license to use or exercise intellectual property or other rights held by ROHM and
other parties. ROHM shall bear no responsibility whatsoever for any dispute arising from the
use of such technical information.

The Products specied in this document are intended to be used with general-use electronic
equipment or devices (such as audio visual equipment, ofce-automation equipment, commu­nication devices, electronic appliances and amusement devices).

The Products specied in this document are not designed to be radiation tolerant.

While ROHM always makes efforts to enhance the quality and reliability of its Products, a
Product may fail or malfunction for a variety of reasons.

Please be sure to implement in your equipment using the Products safety measures to guard
against the possibility of physical injury, re or any other damage caused in the event of the
failure of any Product, such as derating, redundancy, re control and fail-safe designs. ROHM
shall bear no responsibility whatsoever for your use of any Product outside of the prescribed
scope or not in accordance with the instruction manual.

The Products are not designed or manufactured to be used with any equipment, device or
system which requires an extremely high level of reliability the failure or malfunction of which
may result in a direct threat to human life or create a risk of human injur y (such as a medical
instrument, transportation equipment, aerospace machiner y, nuclear-reactor controller, fuel­controller or other safety device). ROHM shall bear no responsibility in any way for use of any
of the Products for the above special purposes. If a Product is intended to be used for any
such special purpose, please contact a ROHM sales representative before purchasing.

If you intend to export or ship overseas any Product or technology specied herein that may
be controlled under the Foreign Exchange and the Foreign Trade Law, you will be required to
obtain a license or permit under the Law.

Notice

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R1120

A