The U2893B is a monolithic integrated circuit. It is
realized using TEMIC’s advanced silicon bipolar UHF5S
technology. The device integrates a mixer, an I/Q modulator, a phase-frequency detector (PFD) with two
synchronous-programmable dividers, and a charge pump.
The U2893B is designed for cellular phones such as GSM,
DCS1800, and PCS1900, applying a transmitter-archi-
tecture where the VCO is operated at the TX output
frequency.
U2893B exhibits low power consumption, and the powerdown function extends battery life.
The IC is available in a shrinked small-outline 28–pin
package (SSO28).
U2893B
Features
D
Supply voltage down to 2.7 V
D
Current consumption 40 mA
D
Power-down function
D
Low-current standby mode
D
High-speed PFD and charge pump
D
Integrated dividers
Block Diagram
MDO
NMDO
+
MDLO
I
NI
90
grd
I/Q modulator
NQPU
Q
Benefits
D
High-level RF integration
D
TX architecture saves filter costs
D
Low external part count
D
Small SSO28 package
D
One device for various applications
PUMIX
MIXO
Voltage
reference
Mixer
MIXLO
RF
NRF
ND
NND
RD
NRD
MC
TELEFUNKEN Semiconductors
Rev . A1, 29-Jan-97
N : 1
divider
R : 1
divider
Mode
control
MUX
PFD
GND
Figure 1. Block diagram
CPC
GNDP
Preliminary Information
VSP
CPO
VS1
VS2
VS3
12494
1 (14)
U2893B
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
ББББББББББ
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ББББББББББ
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Pin Description
NI
MDLO
GND
MDO
NMDO
VS1
VSP
CPO
GNDP
CPC
PUMIX
RD
NRD
PinSymbolFunction
1
I
2
3
4
5
6
7
8
9
10
11
12
13
14
12495
Figure 2. Pinning
28
27
26
25
24
23
22
21
20
19
18
17
16
15
Q
NQ
VS3
MIXO
GND
NRF
RF
VS2
MIXLO
PU
GND
NND
ND
MC
1
2
3
4
5
6
7
8
9
10
I
NI
MDLO
GND
MDO
NMDO
VS1
VSP
CPO
GNDP
CPC
Á11ÁÁÁ
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
1)
PUMIX
RD
NRD
MC
ND
NND
GND
PU
MIXLO
VS2
RF
NRF
GND
MIXO
VS3
NQ
Q
All GND pins must be connected to GND
In-phase baseband input
Complementary to I
I/Q-modulator LO input
1)
Negative supply
I/Q-modulator output
Complementary to MDO
Sink current
Power-up input PU (power-up for all functions, except mixer)
Settling time
ББББББ
High level
Low level
High-level current
Low-level current
Power-up input PUMIX (power-up for mixer only)
Settling time
ББББББ
ББББББ
High level
Low level
High-level current
Low-level current
ББББББ
0.5 to 2 GHz
@ P19
MIXLO
@ P19
= –15 dBm
RF
0.05 to 2 GHz
@ P19
MIXLO
@ P19
MIXLO
CPC open
2.23 kΩ CPC to GND
760 Ω CPC to GND
(I
– I
CPOSI
БББББББ
I
CPOSO
I
БББББББ
CPOSI
D
|
I
6)
CPC grounded
CPOSO
= I
sourc
= I
sink
I
CPO
||
CPO
VMC = VS
Output power within
10% of steady state
БББББББ
values
Active
Standby
Active, V
PUH
Standby, V
Output power within
БББББББ
10% of steady state
БББББББ
values
Active
Standby
Active, V
Standby ,
БББББББ
V
PUMIXL
PUMIXH
= 0.4 V
= –10 dBm
= –17 dBm
= –17 dBm
)/I
D
VSP
= 2.7 V
= 0.4 V
PUL
= 2.7 V
CPOSI
VSP
ÁÁÁÁ
ÁÁÁÁ
|
ÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁ
P19
SP19
P19
P19
CS19
| I
| I
CPO 2
| I
CPO_4
Tk_| I
M
S
C
| I
CPCK
I
S
V
V
I
I
V
PUMIXH
V
PUMIXL
I
PUMIXH
I
PUMIXL
RF
RF
MIXLO
MIXO
MIXO
|
CPO
|
CPC
ICPO
ICPO
CPC
|
MC
PU
PUH
PUL
PUH
PUL
|
|
–20
0.8
1.6
3.6
ÁÁ
ÁÁ
ÁÁ
500
2
ÁÁ
2.5
0
0.1
–10
ÁÁ
ÁÁ
2.5
0
0.1
–10
ÁÁ
U2893B
–17
–40
–8
55
1
2
4
ÁÁ
ÁÁ
ÁÁÁÁÁ
2.7
20
5
ÁÁ
5
ÁÁ
ÁÁ
ÁÁÁÁÁ
1.2
2.4
4.4
15
10
ÁÁ
ÁÁ
0.1
3.7
10
ÁÁ
0.4
0.6
0
10
ÁÁ
ÁÁ
0.4
0.6
0
dBm
dBm
dBm
mVeff
dBc
mA
mA
mA
%/100 k
%
ÁÁ
ÁÁ
–
ÁÁ
pF
mA
m
A
m
s
ÁÁ
V
V
mA
mA
m
s
ÁÁ
ÁÁ
V
V
mA
mA
ÁÁ
6)
See figures 6 and 14.
TELEFUNKEN Semiconductors
Rev . A1, 29-Jan-97
5 (14)
Preliminary Information
U2893B
Supply Current of the Charge Pump
i(VSP) vs. Time
Due to the pulsed operation of the charge pump, the current into the charge-pump supply pin VSP is not constant.
Depending on I (see figure 6) and the phase difference at
the phase detector inputs, the current i(VSP) over time varies. Basically , the total current is the sum of the quiescent
current, the charge-/discharge current, and – after each
phase comparison cycle – a current spike (see figure 3).
up
down
5I
i(VSP)
3I
I
t
2I
i(CPO)
–2I
Figure 3. Supply current of the charge pump = f(t)
Internal current, I, vs. current out of pin CPC
t
Initial Charge Pump Current after
Power-Up
Due to stability reasons, the reference current generator
for the charge pump needs an external capacitor (>500 pF
from CPC to GND). After power-up, only the on-chip
generated current I = I
external capacitor. Due to the char ge pump’s architecture,
the charge pump current will be 2 I = 2 I
the voltage on CPC has reached the reference voltage
(1.1 V). The following figures illustrate this behavior .
The behavior of I(CPO) after power-up can be very
advantageous for a fast settling of the loop. By using
larger capacitors (>1 nF), an even longer period with
maximum charge pump current is possible.
V(CPC)
Vref
I(CPC)
2 I
CPCK
I
CPCK
t
1t0
R
is available for charging the
CPCK
CPC
t
2
CPCK
until
t
I vs. I(CPC)ICPCI
CPC open00.5 mA
2.23 kW to GND–0.5 mA1.0 mA
743 W to GND–1.5 mA2.0 mA
CPC shorted to GNDI
CPCK
>2.0 mA
I
t
1
Time t1 can be calculated as t1 [ (1.1 V C
e.g., C
Time t
e.g., C
= 1 nF, I
CPC
can be calculated as t2 [ (R
2
= 1 nF, R
CPC
= 3.5 A ³ t1 [ 0.3 ms.
max
= 2230 W³ t2 [ 1.1 ms
CPC
Figure 4.
/2230 W) C
CPC
CPC
)/I
t
CPCK
CPC
6 (14)
TELEFUNKEN Semiconductors
Rev . A1, 29-Jan-76
Preliminary Information
U2893B
Mode Selection
The device can be programmed to different modes via an external resistor (including short, open) connected between
Pin MC and VS2. The mode selection controls the N-, R-divider ratios, and the polarity of the charge pump current.
Mode SelectionN-DividerR-DividerCPO Current PolarityApplication
For some of the baseband ICs it may be necessary to
reduce the I/Q voltage swing so that it can be handled by
the U2893B. In those cases, the following circuitry can be
used.
I
Figure 12. Interfacing the U2893B to I/Q baseband circuits
NI
Q
NQ
R1
R1
R1
R1
R2
R2
NI
Q
NQ
I
U2893BBaseband IC
12496
U2893B
U2893B
1 nF
CPC
R1R2
R1 = 2230 R
R2 = 1160 R (incl. rds_on of FET)
4 mA
2 mA
GND
Figure 14. Programming the charge pump current
12497
Application examples for programming different modes.
U2893BU2893B
VS2
RMODE
a) single modeb) any mode & mode 5
RMODE
c) any moded) mode 5 & mode 3 or mode 4
MC
RMODE 1
RMODE 2
VS2VS2
MC
Figure 13. Mode control
RMODE
36k or
VS2
MC
U2893BU2893B
MC
10k
TELEFUNKEN Semiconductors
Rev . A1, 29-Jan-97
9 (14)
Preliminary Information
U2893B
Ì
Test Circuit
<450 mV
1.35 V –
VS1/2 + 0.1 V
Modulator
pp
VAC
VDC
50
LO input
Modulator
outputs
VS
50
VSP
VDO
PFD
Pulse output
PFD input
50
Bias voltage for
VS
charge pump output:
0.5 V < VDO < VSP – 0.5 V
1 n
50
50
1
I
2
NI
3
MDLO
4
GND
5
MDO
6
NMDO
7
VS1
8
VSP
9
CPO
10
GNDP
11
CPC
12
PUMIX
13
RD
14
NRD
Power-up
Baseband inputs
Mode control
Q
NQ
VS3
MIXO
GND
NRF
RF
VS2
MIXLO
PU
GND
NND
ND
MC
VS2
R1
R2
R3
28
27
26
25
24
23
22
21
20
19
18
17
16
15
50
50
<450 mV
VAC
1.35 V –
VDC
VS1/2 + 0.1 V
VS
VS
pp
Mixer
output
Mixer
input
Mixer
LO input
PFD input
13315
10 (14)
Figure 15. Test circuit
TELEFUNKEN Semiconductors
Rev . A1, 29-Jan-76
Preliminary Information
Application Circuit (900 MHz)
Baseband processor
U2893B
f_Ref
v
rms
Dr
= 55 mV
2.7 to 3.5 V
Dr
4.7p
47nH
47nH
1k
NRD
MDO
NMDO
ND
NND
RD
50
MC
I
+
N : 1
divider
R : 1
divider
Mode
control
NI
MDLO
90
grd
I/Q modulator
Q
MUX
GND
NQ
200
PUMIX
PFD
U2893B
27n
12p
PU
Voltage
reference
12p
CPC
MIXO
Mixer
Charge pump
LO (–10 dBm)
1192 MHz
MIXLO
GNDP
RF
NRF
VSP
CPO
VS1
VS2
VS3
to 3.5 V
68p
50
2.7
2.7 to 3.5 V
Figure 16. Power-up, charge pump control, and mode control must be connected according to the application used
VCO
3.3n
390
390
10
6 dB
attn.
MQE 550
To PA
13316
TELEFUNKEN Semiconductors
Rev . A1, 29-Jan-97
11 (14)
Preliminary Information
U2893B
Measurements
Modulation-Loop Settling Time
As valid for all PLL loops the settling time depends on
several factors. The following figure is an extraction from
measurements performed in an arrangement like the application circuit. It shows that a loop settling time of a few
m
s can be achieved.
CPC: 1 kΩ to GND
CPC ‘open’
Vertical: VCO tuning voltage 1 V/Div
Horizontal: Time 1 ms/Div
Figure 17.
Modulation Spectrum & Phase Error
The figure of the TX spectrum and the phase error distribution, respectively, shows the suitability of the
modulation-loop concept for GSM.
technical drawings
according to DIN
specifications
0.15
13018
TELEFUNKEN Semiconductors
Rev . A1, 29-Jan-97
13 (14)
Preliminary Information
U2893B
Ozone Depleting Substances Policy Statement
It is the policy of TEMIC TELEFUNKEN microelectronic GmbH to
1. Meet all present and future national and international statutory requirements.
2. Regularly and continuously improve the performance of our products, processes, distribution and operating systems
with respect to their impact on the health and safety of our employees and the public, as well as their impact on
the environment.
It is particular concern to control or eliminate releases of those substances into the atmosphere which are known as
ozone depleting substances (ODSs).
The Montreal Protocol ( 1987) and its London Amendments (1990) intend to severely restrict the use of ODSs and
forbid their use within the next ten years. Various national and international initiatives are pressing for an earlier ban
on these substances.
TEMIC TELEFUNKEN microelectronic GmbH semiconductor division has been able to use its policy of
continuous improvements to eliminate the use of ODSs listed in the following documents.
1. Annex A, B and list of transitional substances of the Montreal Protocol and the London Amendments respectively
2. Class I and II ozone depleting substances in the Clean Air Act Amendments of 1990 by the Environmental
Protection Agency (EPA) in the USA
3. Council Decision 88/540/EEC and 91/690/EEC Annex A, B and C (transitional substances) respectively.
TEMIC can certify that our semiconductors are not manufactured with ozone depleting substances and do not contain
such substances.
We reserve the right to make changes to improve technical design and may do so without further notice.
Parameters can vary in different applications. All operating parameters must be validated for each customer
application by the customer. Should the buyer use TEMIC products for any unintended or unauthorized
application, the buyer shall indemnify TEMIC against all claims, costs, damages, and expenses, arising out of,
directly or indirectly, any claim of personal damage, injury or death associated with such unintended or