Philips UBA1710M Datasheet

INTEGRATED CIRCUITS

DATA SH EET

UBA1710M

Modulator for GaAs power
amplifiers

Product specification
Supersedes data of 1997 Feb 18
File under Integrated Circuits, IC17

1997 Oct 17

Philips Semiconductors Product specification

Modulator for GaAs power amplifiers UBA1710M

FEATURES

• Power MOS modulators for control of GaAs power
amplifier drain voltage

• Power control loop amplifier and MOS driver

• Voltage tripler for supply of MOS driver

• Positive-to-negative DC converter for GaAs power

amplifier gate biasing.

APPLICATIONS

• Control of GaAs power amplifiers for GSM and DCS
hand-held transceivers.

QUICK REFERENCE DATA

SYMBOL PARAMETER

V

CC

V

DD

I

CC+IDD

T

amb

analog supply voltage 4.2 4.8 7.5 V
digital supply voltage 4.2 4.8 7.5 V
peak supply current in power-up mode − 12 − mA
operating ambient temperature −20 − +85 °C

Note

1. For conditions, see Chapter “Characteristics”.

(1)

GENERAL DESCRIPTION

The UBA1710M integrates the functions required to
operate the GaAs Power Amplifiers (PAs) from the
CGY20xx family which are intended for GSM and DCS
applications.

It includes a negative supply for PA gate biasing and most
of the functions required to implement power control so
that only a very few external component are required.
The power control section integrates two power MOS
devices for control of the PA drain voltages, an MOS driver
and a feedback loop amplifier. The MOS driver is supplied
from an on-chip voltage tripler.

MIN. TYP. MAX. UNIT

ORDERING INFORMATION

PACKAGE

TYPE NUMBER

NAME DESCRIPTION VERSION

UBA1710M SSOP20 plastic shrink small outline package; 20 leads; body width 4.4 mm SOT266-1

1997 Oct 17 2

Philips Semiconductors Product specification

Modulator for GaAs power amplifiers UBA1710M

BLOCK DIAGRAM

TC1

handbook, full pagewidth

D1B
D1A

S1B
S1A

D2
S2

TC1

689

16
15

14
13

18
17

TC2

P

N

VOLTAGE TRIPLER

POWER MOS 1

POWER MOS 2

PINNING

SYMBOL PIN DESCRIPTION

NC3
NC3
V

N

V

CC

P
N

1 charge pump tank capacitor
2 charge pump tank capacitor
3 negative bias voltage

4 analog supply voltage
GND 5 ground
TC1
V

DD

TC1
TC2
TC2
V

P

N

P
N
P

6 charge pump tank capacitor

7 digital supply voltage

8 charge pump tank capacitor

9 charge pump tank capacitor

10 charge pump tank capacitor

11 positive tripler voltage
BUFI 12 buffer input
S1A 13 power MOS 1 source A
S1B 14 power MOS 1 source B
D1A 15 power MOS 1 drain A
D1B 16 power MOS 1 drain B
S2 17 power MOS 2 source
D2 18 power MOS 2 drain
R

ext

19 external resistance for V
STB 20 standby input (active HIGH)

TC2

V

N

P

10 11

STB

P

CLOCK

BUFFER

475 12

V

V

CC

Fig.1 Block diagram.

handbook, halfpage

N

NC3

20

NEGATIVE DC-DC

UBA1710M

MANAGEMENT

GND BUFI

DD

NC3

N

2

CONVERTER

POWER

NC3

NC3

TC1

TC1
TC2
TC2

V

N

P

13

MGG536

1

P

2

N

V

3

N

V

4

CC

GND

5

UBA1710M

6

N

V

7

DD

8

P

9

N

10

P

19

Fig.2 Pin configuration.

R

ext

MGG535

STB

20
19

R

ext

18

D2

17

S2

16

D1B
D1A

15

S1B

14

S1A

13

BUFI

12

V

11

P

1997 Oct 17 3

Philips Semiconductors Product specification

Modulator for GaAs power amplifiers UBA1710M

FUNCTIONAL DESCRIPTION
Power control section

Power control for GaAs PAs from the CGY20xx family is
achieved by varying the drain voltage. This is achieved
with the UBA1710M by means of the two power MOS
devices integrated on-chip. They enable separate control
of the PA output stage from the pre-amplifier stages.
They have a very low ‘on’ resistance for low drop voltage
at high RF output power.

The standard value is typically −2 V, without any external
resistor connected. The other one is a voltage tripler and
is required to supply the MOS driver. The driver is required
to raise the MOS gate voltage well above the battery
voltage in order to open the MOS switches
(‘high side’ driver).

These DC-DC converters are operated at a typical
frequency of 600 kHz supplied by an internal oscillator.
Five external capacitors with a typical value of 0.1 µF
(0603 SMD) are required to operate these converters.

The MOS devices are driven by a buffer. The buffer
amplifier, in association with power MOS, is included in a
feedback loop to exhibit a high cut-off frequency (3 MHz)
over the whole control dynamic range. This buffer allows
fast switching of the MOS in accordance with GSM power
ramping requirements.

DC-DC converters

One DC-DC converter is required to provide negative gate
biasing to the GaAs PA.

Power management

The power management disables the PA drain voltage and
prevents the PA from burnout if drain voltage is supplied
before the negative gate voltage is available.

Standby mode

An additional feature includes a standby mode, reducing
the current consumption to a maximum value of 1 µA.

LIMITING VALUES

In accordance with the Absolute Maximum Rating System (IEC 134); general operating conditions applied.

SYMBOL PARAMETER MIN. MAX. UNIT

V

CC

V

DD

V

I

analog supply voltage −0.5 +9.0 V
digital supply voltage −0.5 +9.0 V
DC input voltage

all pins (except BUFI) −0.5 +9.0 V
pin BUFI −0.5 +5.0 V

I

I

P

tot

T

stg

T

amb

DC current into any signal pin −10 +10 mA
total power dissipation − 0.65 W
storage temperature −65 +150 °C
operating ambient temperature −20 +85 °C

THERMAL CHARACTERISTICS

SYMBOL PARAMETER VALUE UNIT

R

th j-a

thermal resistance from junction to ambient 100 K/W

1997 Oct 17 4