HEI GM0936TQ Datasheet

Features

GM0936TQ

GM0936TQ

Voice-Band Audio CODEC for CDMA

• Single 3-V operation

• Low power consumption

– Operating mode .... 20mW Typ

– Power-down mode ... 1mW Typ

• Combined A/D, D/A, and Filters

• Electret microphone bias reference

voltage available

• Compatible with all digital signal

processors (DSPs)

• Programmable volume control

• 300 Hz - 3.6 kHz Passband with Specified

Master clock

20 DIP/SOP

(TOP VIEW)

____

PDN
EARA
EARB

EARGS

Vcc

__________

MICMUTE

NC
DIN
FSR

__________

EARMUTE

1
2
3
4
5
6
7
8
9

10

20
19
18
17
16
15
14
13
12
11

MICBIAS

MICGS

MICIN

VMID
GND
NC
NC
DOUT
FSX

CLK

NC
NC
NC

AVcc

NC
NC
NC
NC

DVcc

NC

__________
MICMUTE

NC

• Designed for standard 2.048MHz master
clock for U.S. Analog, U.S. Digital, CT2,
DECT, GSM, and PCS Standards for
Hand-held Battery-Powered Telephones

• On-chip voltage references

• Package Type : 48 LQFP, 20 DIP, 20 SOP

48 LQFP

(TOP VIEW)

____

10
11
12

NC

NC

EARGS

484746

1
2
3
4
5
6
7
8
9

PDN

EARB

EARA

4443424140

45

MICIN

MICBIAS

MICGS

EXTMIC

MICSEL

38

39

NC

37

36
35
34
33
32
31
30
29
28
27
26
25

VMID
NC
AGND
NC
NC
NC
NC
NC
NC
DGND
NC
NC

131415

NC

NC

DIN

16

FSR

17

18

NC

CLK

__________

EARMUTE

20

21

23

24

FSX

22

NCNCNC

DOUT

19

1

GM0936TQ

Description

The GM0936TQ contains A/D and D/A conversion functions integrated on a single chip, and utilizes
the sigma-delta modulation technique to achieve high resolution data conversion and low power
consumption. The GM0936TQ is an ideal analog front end device for high performance voice-band
communication systems. Cellular telephone systems are targeted in particular; however, these
integrated circuits can function in other systems including digital audio, telecommunications, and data
acquisition.

The transmit section is designed to interface directly with an electret microphone element. One of two
microphone input signals, MICIN and EXTMIC, is selected by MICSEL. If MICSEL is floated or
Low, then MICIN is selected, and if MICSEL is high, then EXTMIC is selected. The microphone input
signal (MICIN and EXTMIC) is buffered, first-order low-pass filtered, and amplified with provision for
setting the amplifier gain to accommodate a range of signal input levels. The amplified signal is 1bit­modulated by second-order sigma-delta modulator. The modulated signal is then applied to the input of
high-performance FIR-type digital decimation filters with frequency response equalization. The
resulting data is then clocked out of DOUT as a serial data stream.

The receive section takes a frame of sereal data on DIN and converts it to analog through high­performance FIR-type digital interpolation filter together with frequency response equalization,
second-order digital sigma-delta modulator, and analog reconstruction filters.

On-chip voltage reference ensures a highly integrated solution and all internal voltage references are
generated. An internal reference voltage, VMID, is used to develop the midlevel virtual ground for all
the amplifier circuits and the microphone bias circuit.Another reference voltage, MICBIAS, can supply
bias current for the microphone.

Serial DSP interfaces for transmit and receive paths support directly industry standard DSP processors.

The GM0936TQ devices are characterized for operation from -20 to 70¡É.

2

Block Diagram

AV

CC

AGND DV

CC

DGND

GM0936TQ

_ __
PDN

EXTMIC

MICIN

MICGS

__________

EARMUTE

MICMUTE

VMID

MICBIAS

EARGS

EARA

EARB

Analog 2nd orderΣ -

x

ANALOG

Σ ∆-MODULATOR

VOLTAGE

REFERENCE

POST

FILTER

∆

Modulator Block Diagram

1-BIT

DAC

MICSEL

Integrator1 Integrator2

DIGITAL Σ ∆-

MODULATOR

1/21/2

SINC 3­FILTER

FIR-

FILTER

INTERFACE

SINC 2­FILTER

Quantizer

CLK

FSR

FSX
DIN

DOUT

FIR-

FILTER

Y

Digital 2nd order Σ -

x

∆

Modulator Block Diagram

2

Quantizer

Y

Delay1Delay2

3

Pin Description

LQFP

SOP&DIP

I/O

ANALOG SIGNALS

GM0936TQ

TERMINAL

NAME
AGND 34 16 Analog Ground

AVcc 4 5 Analog Power (3V)
EARA 44 2 O Earphone output
EARB 45 3 O Side-tone output
EARGS 46 4 I Side-tone input
EARMUTE_ 17 10 I Earphone output mute control signal
MICBIAS 42 20 O Microphone bias
MICGS 41 19 O Output of the internal microphone amplifier
MICIN 40 18 I Microphone input
MICMUTE_ 11 6 I Microphone input mute

VMID 36 17 O

ETMIC 39 N/A I Hand-free MIC-IN

DESCRIPTION

Bias voltage reference. A pair of external, low­leakage, high-frequency capacitors (1 µF and
470 pF) should be connected between VMID
and ground for filtering

MICSEL 38 N/A I

MIC-IN selection input. When float or
low, MICSEL selects MICIN. When high,
MICSEL selects EXTMIC.

4

Pin Description

LQFP

SOP&DIP

I/O

1,2,3,

5,6,7,

12,13,

14,18,

22,23,

24,25,

26,28,

29,30,

31,32,

33,35

DIGITAL SIGNALS

GM0936TQ

TERMINAL

NAME
CLK 19 11 I Clock input (2.048 MHz)

DGND 27 16 Digital ground
DIN 15 8 I Receive data input
DOUT 21 13 O Transmit data output
DVcc 9 5 Digital power (3 V)

FSR 16 9 I

FSX 20 12 I

PDN_ 43 1 I Power-down input, Active Low

8,10,

NC

7, 14, 15 No internal connection

DESCRIPTION

Frame-synchronization clock input for
receive channel

Frame-synchronization clock input for
receive channel

5

Electrical Characteristics

Absolute Maximum Ratings over operating free-air temperature range

GM0936TQ

SYMBOLPARAMETER MIN MAX UNIT

Supply Voltage Range V

Digital Input Voltage Range - 0.3 V

Analog Input Voltage Range - 0.3 V

DVCC,AV

V

ind

V

ina

CC

- 0.3 3.6

TYP

3.6

3.6

Recommended Operating Conditions

SYMBOLPARAMETER MIN MAX UNIT
Supply Voltage 3.3 V
High-level Input Voltage V

Low-level Input Voltage
Operating free-air

Temperature

Power Supply Characteristics, f

DVCC,AV

V

IH

V

IL

T

A

CC

2.2

-20 70

= 2.048 MHz, outputs not loaded, Vcc=3V, TA=25¡É

CLK

PARAMETER MIN MAX UNIT

TYP

3.02.7

0.8

TYP

V

¡É

Power Dissipation , Operating mW
Power Dissipation , Power down

Digital Characteristics (T

=25¡É , DVCC= AV

A

CC

= 3V)

PARAMETER MIN MAX UNIT

18

1

TYP

Input Capacitance 10 pF
Input Leakage Current - 10 10
Low-level output Voltage (IOL= 3.2mA) 0.4 V
High-level output Voltage (IOH= -3.2mA) 2.4 V

6

mW

§Ë

Microphone interface

GM0936TQ

IIB Input bias current at MICIN
B1 Unity-gain bandwidth, open loop at MICIN

Av Large-signal voltage amplification at MICGS

Iomax Maximum

output current

VMID

TEST CONDITIONSPARAMETER MIN MAX UNIT

V I= 0 to 3 VVIO Input offset voltage at MICIN mV

TYP

1.5

10000

3
1MICBIAS(source only)

Speaker interface

TEST CONDITIONSPARAMETER MIN MAX UNIT
VO(PP) AC output voltage Vpp
IOmax Maximum output current

ro Output resistance at EARA, EARB

Gain change

RL = 600 Ω

EARMUTE low, max level
when muted

TYP

1

-60

+5

+200

3

+1

nA
MHz
V/V

µA

mA

mA

Ω

dB

7